Peptides

<p>Peptide derived from the Sialokinin neuropeptide which is involved in smooth muscle contraction. It is homologous to mammalian Substance P and was first identified in mosquito Ae. Aegypti.</p>

<p>The Histone H3 (20-36)-K27Me3 is derived from Histone 3 (H3) which is one of the four core histones (H2A, H2B, H3 and H4) fundamental in compacting eukaryotic DNA into the nucleosome. The nucleosome arises when 147 base pairs of DNA wrap around a H3-H4 tetramer and two H2A-H2B dimers, forming the histone octamer core. Both H4 and H3 are highly conserved and perform roles in binding to segments of DNA which enter and leave the nucleosome and in chromatin formation. Similar to the other core histone, H3 has a globular domain and a flexible N-terminal domain, 'histone tail' which can undergo modifications such as acetylation, methylation, phosphorylation and ubiquitination. Due to histones containing a large number of lysine and arginine residues they have a positive net charge which interacts in an electrostatic manner with the negatively charged phosphate groups in DNA. The transcriptional activation or silencing of the chromatin is controlled by ATP-dependent chromatin remodelling factors and histone modifying enzymes which target histone proteins. Both processes function to alter to change the positioning of the nucleosome, allowing the DNA it to be either available to the transcription machinery or inaccessible.The Histone H3 (20-36) lysine 27 has been trimethylated which is usually a marker of repressive chromatin. H3K27 trimethylation also prevents H3 from interacting with SET1-like complexes, thus inhibiting the trimethylation of H3K4.</p>

<p>PD-1 (27-41) peptide is derived from the programmed cell death-1 (PD-1) which interacts with its ligand, PD-L1 to regulate immune homeostasis. PD-1 and its ligand PD-L1 are critical in regulating T cell activation, tolerance and immuno-pathology. PD-1 is an immune checkpoint and guards against autoimmunity through two mechanisms. First, it promotes apoptosis of antigen-specific T-cells in lymph nodes. Second, it reduces apoptosis in regulatory T cells.Several types of cancer cells overexpress PD-L1 in order to escape from the PD-1/PD-L1 immuno-surveillance mechanism. Consequently PD-1 inhibitors and PD-L1 inhibitors could be used as a therapeutic in the treatment of cancers.</p>

<p>TentaGel; resins are grafted copolymers consisting of a low cross-linked polystyrene matrix on which polyethylene glycol (PEG or POE) is grafted. The PEG spacer is attached to the matrix via an ethyl ether group which increases stability towards acid treatment and minimizes PEG-leaching. As PEG is a "chameleon type" polymer with hydrophobic and hydrophilic properties, the graft copolymer shows modified physico chemical properties which are highly dominated by the PEG moiety (and no longer by the polystyrene matrix). These graft copolymers are pressure stable and can be used in batch processes as well as under continuous flow conditions. The PEG spacer is in the range of M.W. 3000 Da. The micro spherical shape and the monosized character of this resin allow applications in automated sorters, for creating huge libraries, high speed synthesis etc.<br>Particle size: 20 µm monosized capacity: 0.2 - 0.3 mmol/g.</p>

<p>YSA binds to the extracellular domain of ephrin type-A receptor 2 (EphA2) with high affinity and selectivity. YSA binding activates EphA2 and its tumour suppressing downstream signalling pathways (including inhibition of the PI3K/Akt and ERK pathways), and promotes receptor internalisation.EphA2 is highly expressed in many types of solid tumour, and the level of EphA2 expression is positively correlated with malignancy and poor prognosis in some cancer types.YSA has been shown to be an effective targeting peptide of chemotherapeutic drugs to EphA2 expressing tumours. YSA-drug conjugates are able to selectively target EphA2 expressing tumours, both activating tumour supressing downstream signalling pathways, and becoming effectively internalised by cancer cells to further increase the potency of the chemotherapeutic drug. YSA-drug conjugates have been shown to be dramatically more effective at inhibiting tumour growth than chemotherapy alone. Selective tumour targeting with YSA could also reduce the systemic toxicity caused by nonselective and highly toxic chemotherapy agents, and thus reduce adverse side effects of chemotherapy.The uncharged C-terminal amide has the potential to increase the biological activity of this peptide.</p>

<p>PTH 1-34, is a biologically active peptide fragment of parathyroid hormone (PTH). PHT 1-34 has been shown to enhance bone fracture healing by promoting osteogenesis. PTH 1-34 also has chondrogenic properties.PTH is an 84-amino-acid polypeptide hormone (PTH 1-84) which is secreted by the parathyroid glands along with its fragments (such as PTH 1-34 and PTH 7-84). PTH increases calcium and decrease phosphate levels in the blood and the abundance of PTH-derived peptides is regulated by blood calcium levels. PTH inhibits the bone growth-promoting activity of osteoblasts and induces osteoclasts to resorb bone and release calcium and phosphate ions into the blood. PTH binds to and activates the receptor parathyroid hormone receptor 1 (PTHR1). PTHR1 is a G-protein-coupled receptor (GPCR) which regulates mineral ion homeostasis, bone turnover and skeletal development.</p>

<p>Galanin is a neuropeptide synthesised and released by the brainstem locus coeruleus (LC). Galanin is expressed in most LC neurons in rodents and humans. Galanin has been shown to inhibit LC activity by hyperpolarising LC neurons, suppressing their spontaneous firing rate, and enhancing alpha2-adrenergic receptor-mediated negative feedback. Galanin is also a potent trophic and neuroprotective factor throughout the nervous system.Galanin is widely distributed from the central nervous system, peripheral regions and endocrine system. Galanin's overarching function is as an inhibitory, hyper-polarizing neuromodulator for classical neurotransmitters like acetylcholine and serotonin. Galanin interacts with 3 receptor subtypes GalR1-3 which are G protein-coupled receptors and are inserted into the plasma membrane. GalR1 is believed to activate a Gβγ pathway to regulate MAPK activation. GalR2 can also activate the MAPK pathway but unlike GalR1 there is detectable inositol phosphate production. GalR3 is associated with the Gα pathway, activation of the receptor leads to cellular influx of K+. Each receptor has been associated with neurological diseases such as GalR3 and epilepsy.Galanin protects against a variety of physiological insults in vitro, including excitotoxicity and β-amyloid toxicity. Changes in galanin have been widely studied in relation to Alzheimer's disease and galaninergic neurons have been shown to be spared in late-stage Alzheimer's relative to non-galaninergic neurones.</p>

<p>Soybean trypsin inhibitor inhibits trypsin, factor Xa, plasmin, and plasma kallikrein activity in serum-free cell culture media. It does not inhibit metallo-, cysteine, aspartic proteases, or tissue kallikrein (serine proteases).Kallikreins (KLKs) are a large family of secreted serine proteases with either trypsin-like or chymotrypsin-like specificity which carry out many biological functions. The KLK proteases are involved in pathways that regulate skin desquamation, tooth enamel formation, kidney function, seminal liquefaction, synaptic neural plasticity, and brain function. Disruptions in the function of KLK activity has been linked to several pathologies, including respiratory diseases, neurodegeneration, anxiety, schizophrenia, skin-barrier dysfunction, pathological inflammation, and cancer.</p>

<p>Relaxin-3 is part of the insulin/relaxin superfamily with various roles, including appetite, stress, and addiction. Relaxin-3 binds to its cognate receptor relaxin family peptide 3 receptor (RXFP3). B1-22R  is a single-chain relaxin-3 antagonist for RXFP3 no interaction is found with RXFP1 or RXFP4. B1-22R  is a truncation of the B-chain of relaxin-3 and the addition of an arginine residue at the C-terminus-B1-22R acts as a RXFP3 antagonist. B1-22R has been used to perform structural analysis relationships (SARs) and residue scanning to understand the critical residues and conformation of the interaction between B1-22R and RXFP3. B1-22R can generate more potent analogs of relaxin-3 that are more stable and serve as models for drug design targeting the relaxin-3 receptor for regulation of addiction, stress, and appetite.B1-22R is provided in the amide form.</p>

<p>CBL (167-180) is derived from the CBL E3 ubiquitin ligase which targets receptor tyrosine kinases to lysosome degradation. CBL and its family member CBL-B are expressed in hematopoietic cells and as E3 ubiquitin ligases they contain a tyrosine kinase domain and an RF domain joined by a linker domain. The function of the RF domain is to transfer ubiquitin from E2 ubiquitin-conjugating enzymes onto the target protein which is often phosphorylated. Consequently the ubiquitinated substrate, the receptor tyrosine kinases, are ultimately targeted to the lysosome for degradation.EGFR is an example of a receptor tyrosine kinase whose activation is prevented by CBL and CBL-B when they bind and recruit GRb2, the adapter protein to EGFR. Consequently the ubiquitinylation of EGFR occurs and targets it for recognition by the endosomal protein complex and then lysosome degradation.It has also been found that the CBL family can negatively regulate through ubiquitinylation, PI 3-kinases, Rap G-protein guanine nucleotide exchange factor (GEF), C3G and Rho GTPase GEF Vav which are all non-receptors.If CBL becomes non-functional it can be associated with malignancies such as acute myeloid leukemia and myelodysplastic syndrome.</p>

IL-13 is a cytokine that belongs to the IL-4 family of cytokines. IL-13 is an activator of B cells and mast cells. It binds to the IL-4 receptor and can activate lymphocytes, macrophages, eosinophils, basophils, and neutrophils. This cytokine has been shown to inhibit ion channels in airway epithelium cells and also bind to the alpha1 subunit of the N-methyl d-aspartate receptor. IL-13 is also a ligand for the IL-4 receptor, which may be important for its function as a regulator of other cytokines such as TNFα or IFNγ.

<p>Haemagglutinin (HA) peptide YPYDVPDYA – HA Tag</p>

<p>Gastrin-1 Rat.</p>

<p>Tetanus Toxin (1174-1189) is a protein that is derived from the single-chain polypeptide neurotoxin produced by Clostridium tetani. The neurotoxins produced by Clostridium tetani are among the most potent molecules known to humankind. Once in the body, the toxin binds to the basal lamina at the neuromuscular junction. From here, the toxin is transported to inhibitory interneurons in the spinal cord, where it prevents the release of neurotransmitters, which causes spastic paralysis.</p>

<p>Portion of Influenza NP</p>

HiGom is a venom that belongs to the group of proteins that can produce reactive oxygen species. It has been shown to inhibit mitochondrial membrane potential, cellular viability, and the production of reactive oxygen species. HiGom has also been shown to inhibit the production of inflammatory cytokines and chemokines in response to chronic pain. This protein may be useful for cancer treatment as it has been shown to inhibit tumor growth by inducing apoptosis and inhibiting angiogenesis.

Suc-Glu-Ala-Leu-Phe-Gln-pNA is a substrate for human rhinovirus 3C protease. The peptide is a mixture of four amino acids and has been synthesized to serve as an inhibitor of the HRV3C protease enzyme. Suc-Glu-Ala-Leu-Phe-Gln-pNA is expected to inhibit the HRV3C protease by binding to the active site, thereby preventing cleavage of viral proteins that are needed for replication.

<p>EBV BRLF1 (148-156) (HLA-A3) is an immunodominant CEF control peptide that is derived from the Epstein-Barr virus (EBV). EBV targets B cells, which can cause lytic infection and the consequent death of these cells. Natural killer (NK) cells, invariant (iNKT) cells, CD4T cells and CD8 T cells are essential to control the action of EBV-infected cells. EBV BRLF1 (148-156) (HLA-A3) is defined as a CEF control peptide due to its antigenic properties. Clinically, this peptide is a suitable epitope for CD8+ T cells and can be used to stimulate the release of IFNg. HLA-A3 refers to the cell HLA type that this peptide acts on.The BRLF1 protein is a transcriptional activator that interacts with the amino and carboxy termini of the CREB-binding protein (CBP). CBP activates the lytic EBV gene SM, meaning the interaction between CBP and BRLF1 is responsible for EBV particles switching from latent to lytic viral replication.</p>

H-Asp(OtBu)-2-ClTrt-Resin (200-400 mesh) 1% DVB is a tool for peptide synthesis. It contains a set of building blocks including thiols, alcohols, amines, and resin. The resin is used as the solid support for peptide synthesis. The thiols react with the resin to form a covalent bond that anchors the building blocks to the solid support. The alcohols and amines can be reacted with amino acids or other activated carboxylic acids to synthesize peptides on this type of resin.

<p>This C-terminal Sortagging peptide acts as a (oligo)glycine nucleophile in the final steps of a sortagging protein labelling reaction. This reaction results in the [Cys(AF488)] fluorescent moiety being attached to the C-terminus of the target protein or peptide.A substrate peptide containing the LPXTG motif is recognised and cleaved by the enzyme Sortase A (SrtA) from Staphylococcus aureus. The catalytic cysteine residue in the active site of SrtA, serves as a nucleophile to cleave the peptide bond between threonine and glycine of the substrate peptide. Cleavage results in the formation of a thioacyl intermediate between the substrate peptide and SrtA. This intermediate is then resolved by the N-terminus of this (oligo)glycine nucleophile peptide, resulting in the creation of a new peptide bond that links the substrate peptide to this peptide and its fluorescent dye.  This method of protein labelling is known as sortagging.This peptide contains the AF488 fluorescent dye AF488 is a bright green dye with excitation at 488 nm, it is water soluble and stable from pH 4 to pH 10.</p>

<p>GALA is a synthetic pH sensitive peptide designed to better understand viral fusion proteins interaction with membranes. This could ultimately lead to better drug delivery systems by more efficient cell entry and escape from the endosome to enter the nucleus.GALA is 30 amino acids long, sufficient to span the lipid bilayer. The EALA repeats are designed to create a hydrophobic face that can allow lipid interaction when GALA is in an alpha helical conformation. Glutamic acid is inserted with the EALA repeats to create a pH-dependent negatively charged sidechain.  In neutral pH conditions GALA is in a random coil conformation. In acidic conditions (pH 5) GALA forms an amphipathic helix which can bind to the lipid bilayer. The interaction varies depending on the composition of the lipid membrane. Most importantly, interaction with negative or neutrally-charge bilayers leads to the formation of a transbilayer pore formed of approximately 10 GALA peptides. GALA has already been utilised for this purpose at low pH to deliver genes into the nucleus of cells in vitro. The composition of the membrane effects the formation and bilayer-destabilizing properties of GALA however, GALA has a strong potential for future applications for the delivery of genes, DNA and drugs into the cell.</p>

<p>CBL (598-612) Light.</p>

<p>Fmoc-Trp(Boc)-Wang resin is a solid phase peptide synthesis resin that can be used to synthesize peptides. It contains an amino acid sequence of Trp-Boc-Wang, which has been shown to inhibit the activity of ion channels. Fmoc-Trp(Boc)-Wang resin is also a useful tool for studying protein interactions and receptor binding. This resin is manufactured by Applied Biosystems, Inc., and is available in 100-200 mesh size. The product comes with a 1% DVB content and purity of &gt;97%.</p>

<p>The human oligopeptide transporter (PEPT1) is a critical transporter of dipeptides, tripeptides, and peptide-like drugs, including β-lactam and cephalosporin antibiotics, and ACE inhibitors. Therefore, there is an effort to understand better the transport mechanism and substrate requirements of PEPT1 to improve drug uptake.N-L-Glutamyl-L-Lysine is a dipeptide that naturally occurs in the body during protein degradation. It has been used in functional transport assays with other dipeptides to understand PEPT1 binding specificity with substrates and how this affects the conformation. N-L-Glutamyl-L-Lysine, along with other short peptides, is a vital tool in studying facilitator transporters like PEPT1. N-L-Glutamyl-L-Lysine has two charges and forms an intramolecular salt bridge that places the side chains in close proximity to fit the transporter better. N-L-Glutamyl-L-Lysine has helped understand that PEPT1 doesn't bind all dipeptides, and not all bound peptides are transported. Further work with N-L-Glutamyl-L-Lysine could further define the structure&amp;minus-transport relationships of PEPT1 for better drug transportation.</p>

<p>This 32 amino acid peptide contains a 17 amino acid ring structure that is common to all natriuretic peptides. It is also called the brain natriuretic peptide (BNP) because it was first identified in porcine brain- however, the main source of this peptide is not the brain but the cardiac ventricle. This cardiac neurohormone is secreted from the ventricles in response to volume expansion and pressure overload. It has natriuretic and vasodilatory effects and suppresses the renin-angiotensin-aldosterone system.</p>

<p>Cyclic AC253 is an antagonist of the amylin receptor with neuroprotective effects against Aβ toxicity. Cyclic AC253 eliminates Aβ-induced impairment of hippocampal long-term potentiation and is able to penetrate the blood-brain barrier.</p>

<p>HIV-1 replication is rapid and error prone which is beneficial to the virus as it allows mutations to arise that aid evasion of the host immune system and resistance to drug treatment. RT is the key target for most anti-HIV drugs and therefore conserved sequences are useful to aid further research into new less toxic antiviral treatments.  HIV-1 reverse transcriptase (RT) converts the RNA genome into DNA during retroviral replication. HIV-1 RT is a heterodimer composed of 2 subunits, p66 and p51. HIV-1 RT heterodimer has 2 enzymatic functions, DNA polymerase and Rnase H resulting in nucleic acid translation to a linear DNA duplex. Complete inhibition of viral replication is the only known method of preventing HIV-1 drug resistance and disease progression.HIV RT epitopes have become a useful research tool as an in vitro antigenic challenge to study cytotoxic T lymphocyte (CTL) responses to retroviruses. The HIV-1 RT A2-YI9 sequence has been shown to be an effective epitope for CTL recognition leading to lysis of HIV-infected T cells. The A2-YI9 is also considered a potential for vaccine development due to it being a well conserved sequence. Synthesised HIV-1 RT A2-YI9 is provided here with N-terminal acetylation to mimic the charge of the native peptide more closely. The epitope is also available without acetylation from our catalogue.</p>

<p>Peptide derived from vitronectin, the mammalian glycoprotein which plays a key role in tissue repair and remodelling. Its properties as an adhesive protein allow mammalian cells in serum to interact with culture vessels.</p>

<p>The progress of cardiovascular disease (CVD) comes from the damage and necrosis of cardiomyocytes. Although treatment has improved, once these cells are damaged, they cannot be recovered. Therefore, further research into cardiomyocytes is vital. Cardiomyocytes need to be in an exceedingly pure culture for research work. However, this requires identification of these cells from the ESCs present. With the use of a phage biopanning library, this sequence has been shown to have a high affinity to a receptor on the membrane surface of mouse ESC-derived cardiomyocytes. The functionality of this sequence allows it to be used a conjugate for drug or gene delivery to target cardiomyocytes or to purify cardiomyocytes in a research setting.</p>

<p>Eα antigen peptide, known to bind with high affinity to the major histocompatibility complex (MHC) class II molecule IAb. MHC class II molecules are normally found on antigen presenting cells such as dendritic cells, mononuclear phagocytes, endothelial cells, thymic epithelial cells and B cells and they present antigens derived from extracellular proteins. Eα peptide bound to IAb is specifically recognized by Y-Eα antibody.This peptide contains a C-terminal biotin tag for simple detection and purification.  The linker is ethylenediamine.</p>

<p>Represents the extracellular region of amyloid β peptide (Aβ). This region may be responsible for the conformational changes seen in Aβ and is cytotoxic in vitro.Aβ has been identified as the key subunit of the extracellular plaques found in the brains of patients with Alzheimer disease (AD) and Down syndrome (DS). Aβ has therefore been extensively studied as a potential target for treatment of AD.Aβ is formed from the cleavage of the large, transmembrane protein- APP (amyloid precursor protein). Cleavage of APP by β- and then &amp;γ-secretases results in the formation of Aβ. Aβ can aggregate to produce amyloid-β oligomers, which are thought to be highly neurotoxic. Over time Aβ can further aggregate to produce the characteristic senile plaques present in AD and DS. Aβ can be degraded by enzymes such as neprilysin, insulin degrading enzyme or endothelin converting enzyme. At physiological levels Aβ may be involved in controlling synaptic activity and neuronal survival.</p>

<p>AF12198 is a selective receptor antagonist to the human cytokine, type 1 interleukin-1 (IL-1) and thus blocks IL-1β signalling. AF12198 can inhibit IL-1-induced IL-8 production by human dermal fibroblasts and IL-1-induced intercellular adhesion molecule-1 (ICAM-1) expression by endothelial cells. AF12198 also blocks IL-1 induction of IL-6 and down regulates IL-6 induction in monkeys. AF12198 does not bind the human type II IL-1 receptor, or the murine type I IL-1 receptor.IL-1 influences a wide range of immune and inflammatory responses. Sustained expression of even low levels of IL-1 can be harmful in chronic inflammatory diseases such as rheumatoid arthritis and inflammatory bowel disease.</p>

<p>Reactivity to human leukocyte antigens (HLAs) is a rising concern in clinical treatments such as organ transplant rejection. Understanding the epitopes and the signalling pathways leading to reactivity could produce better clinical therapies in the future. The peptides presented by the non-classical HLA-G are important for a largely tolerogenic role and are considered part of an immune checkpoint. This, therefore, makes understanding ligand characteristics and HLA-G a target for cancer therapies. Interleukin-27 subunit β (22-30) fragment has been identified as an epitope that human leukocyte antigen HLA-G naturally presents, determined by liquid chromatographic tandem mass spectrometry (LC-MS/MS). This epitope has been used extensively in the literature to help understand the natural ligand presentation of HLA-G.For example, leukocyte immunoglobulin (Ig)-like receptors (LILRs) are key regulators of the immune response and therefore targets for therapeutics. Inhibitory LILRB1 and LILRB2 with HLA-G are pivotal for immunotolerance during pregnancy and autoimmune diseases plus cancer cell immune evasion. Interleukin-27 subunit β (22-30) fragment was used in binding affinity assays to clarify the conformational plasticity of the interaction between the receptor, the HLA antigen, and the various peptides HLA-G can accommodate.</p>

This peptide is derived from gliadin wheat protein residues 31-43. It elicits an innate immune response by upregulating expression of interleukin (IL)-15 and cyclooxygenase (COX)-2. This peptide also promotes expression of CD25 on monocytes and macrophages, expression of CD83 on dendritic cells, and p38 MAP kinase activation. Treatment with this peptide allows immunodominant epitopes (57-68 and 62-75) to induce T-cell activation and enterocyte apoptosis.

<p>[5-FAM]-ERKtide</p>

H-Asn-2-ClTrt-Resin (100-200 mesh) 1% DVB is a building block for the synthesis of peptides. It is a resin that contains amines, thiols, and alcohols. The resin has a particle size of 100 to 200 mesh and contains 1% DVB.

<p>SARS-CoV-2 Nucleoprotein (331-345)</p>

<p>JAG-1(188-204). Jagged - 1 is a cell surface ligand for in the Notch pathway. Notch receptors and ligands are present on the extracellular service of cells and require cell-cell contact for engagement. Ligand binding to Notch receptors results in the proteolytic cleavage of membrane-bound Notch receptors, thus allowing the intercellular region to be transported to the nucleus and become a transcriptional activator. The ligand-induced Notch activation is regulated by E3 ubiquitin ligases, Mindbomb1 (Mib-1) and Neuralized.JAG1 is widely expressed throughout mammalian development, across many tissues and developmental stages. Notch signalling plays a critical role in cellular fate determination including muscle cell differentiation, neurogenesis, and the development of the sensory regions of the inner ear- heart- kidney- eye- lung and other tissues.Jag-1 has been implicated in breast- cervical- colorectal- endometrial- gastric- head and neck- ovarian- hepatocellular- lung- pancreatic- prostate, and kidney and adrenocortical cancers, leukemia and lymphoma. Co-overexpression of Notch-1 and Jagged-1 predicts the poorest overall cancer survival. JAG1 mutations have also been associated Alagille syndrome.</p>

<p>The coronavirus (CoV) nucleoprotein is the major component of CoV structural proteins. The nucleoprotein has a critical role in virus assembly and RNA transcription. The nucleoprotein is essential in the formation of helical ribonucleoproteins and in regulating viral RNA synthesis. The nucleoprotein can also regulate infected host cellular mechanisms. It is highly expressed during infection and may induce protective immune responses against SARS-CoV and SARS-CoV-2.The nucleoprotein residues GMEVTPSGTWLTYTG (321-335) from SARS-CoV-2 have been identified as a T-cell epitope with a predicted HLA restriction. Immune targeting of confirmed epitopes may potentially offer protection against SARS-CoV-2 and help the development of vaccines for long-lasting immunity.</p>

<p>Antagonist peptide of VEGF-A and VEGF-B reproducing two binding regions of VEGF-B (loop 1 and loop3) linked together by a receptor binding region of VEGF-A (loop3). Binds to both VEGFR1 and VEGFR2 and inhibits VEGF-A driven proliferation, migration and tube formation in HUVECs.</p>

<p>The MHC class II allele I-Ag7 is the allele associated with diabetes in the non-obese diabetic (NOD) mouse. I-Ag7 is also associated with spontaneous mouse models of arthritis and multiple sclerosis. The peptide mimotope mimics the structure of an epitope and therefore causes an antibody response similar to the one elicited by the epitope.</p>

<p>Interactions between ECM proteins and growth factors were only thought to concentrate growth factors and to enhance their multimerisation for signalling. However, recent studies indicate that binding of growth factors to ECM proteins may enhance interactions between multi-domain ECM proteins, such as fibronectin (FN), with cell surface receptors, mostly integrins. The discovery of P12 revealed that a small peptide can mimic the role of FN with PDGF-BB, suggesting that some ECM-growth factor interactions may be less complex. P12 can not only bind to PDGF-BB, but also promote cell survival and improve rat skin burns in a dose dependent manner.P12 may have a clinical potential, especially in the reduction of cell death after tissue damage.</p>

<p>GQPR tetrapeptide.</p>

<p>[Nle12] alpha-factor is a cyclic analog of the Saccharomyces cerevisiae alpha-factor mating pheromone.</p>

<p>Boc-VPR-AMC is a fluorogenic peptide substrate composed of the short peptide chain, Valine-Proline-Arginine (VPR) and the fluorophore, 7-amino-4-methlycoumarin (AMC). Fluorogenic peptide substrates such as Boc-VPR-AMC have high sensitivity and specificity and therefore can be used to detect molecules of interest. For example within the field of scientific forensics, Boc-VPR-AMC can be used to investigate deposits of saliva in situ. When Fluorogenic peptide substrates are incubated with specific enzymes, fluorescence is emitted due to the release of the fluorophore from the peptide-fluorophore bond. When Boc-APR-AMC interacts with its target enzyme, the 7-amino-4-methylcoumarin fluorophore is released causing a fluorescent emission at 440nm.</p>

<p>The coronavirus (CoV) nucleoprotein is the major component of CoV structural proteins. The nucleoprotein has a critical role in virus assembly and RNA transcription. The nucleoprotein is essential in the formation of helical ribonucleoproteins and in regulating viral RNA synthesis. The nucleoprotein can also regulate infected host cellular mechanisms. It is highly expressed during infection and may induce protective immune responses against SARS-CoV and SARS-CoV-2.The nucleoprotein residues TQAFGRRGPEQTQGN (271-285) from SARS-CoV-2 have been identified as a T-cell epitope with a predicted HLA restriction. Immune targeting of confirmed epitopes may potentially offer protection against SARS-CoV-2 and help the development of vaccines for long-lasting immunity.</p>

<p>Residues 1-16 of the gastrointestinal hormone motilin, secreted from endocrine cells in the small intestines, mainly from the jejunum and duodenum, in response to the fasting, drinking water or the mechanical stimulus of eating.</p>

<p>HLA-A*02 is a class I major histocompatibility complex (MHC) allele which is part of the HLA-A group of human major histocompatibility complex (MHC) leukocyte antigens (HLA). HLA-A is a human MHC class I cell surface receptor and is involved in presenting short polypeptides to the immune system. These polypeptides are typically 7-11 amino acids in length and originate from proteins being expressed by the cell. Cytotoxic T cells in the blood "read" the peptide presented by the complex and should only bind to non-self peptides. If binding occurs, a series of events is initiated culminating in cell death via apoptosis. Hepatitis B virus (HBV) polymerase is a multifunctional enzyme that can use both RNA and DNA as a template for amplification and also has an RNase H function. First the polymerase acts on the HBV pre-genomic RNA (pgRNA) to reverse transcribe it to form the (-) DNA strand. Simultaneously the RNA template is degraded by the polymerases RNase H activity, except for a stretch of RNA at 5' end of the pgRNA which is used to prime the synthesis of the (+) DNA strand. This process results in a new partially double-stranded relaxed circular DNA molecule (rcDNA) within a new capsid.</p>

<p>Pantinin-3, like other pantinin peptides, has high activity against Gram-positive bacteria yet weak activity against Gram-negative bacteria. With the exception of S. aureus, pantinin-3 displays the highest activity against all Gram-negative bacteria for which it has been tested. Pantinin-3 also displays activity against Candida tropicalis and has relatively mild haemolytic activity against human red blood cells.</p>

<p>The SARS-CoV-2 non-structural protein 13 (NSP13) has been identified as a target for anti-viral therapeutics due to its highly conserved sequence and is essential for viral replication.  NSP13 is part of the helicase superfamily 1B. As an NTPase and RNA helicase, NSP13 binds to RNA-dependent RNA polymerase and acts in concert with the replication-transcription complex to stimulate backtracking and further activate NSP13 helicase activity. These factors make NSP13 a good target for developing new antiviral drugs. In addition, the identification of epitopes within the NSP13 sequence can help design more effective SARS-CoV-2 vaccines.Models have predicted epitopes exhibiting antigenicity, stability and interactions with MHC class-I and class-II molecules. NSP13 (556-570) is an epitope candidate with various HLA restrictions. This epitope can be used to better vaccine design for more durable CD4+ and CD8+ T cell responses for long-lasting immunity.</p>

<p>LP2</p>

<p>Orexin-A (also known as hypocretin-1) is a hypothalamic neuropeptide that regulates feeding behaviour, reward processes, cognition, the sleep-wake cycle and stress. Orexin-A is involved in stress induced mental illness such as major depressive disorder and anxiety disorders and may therefore be a potential target for treatment of these conditions.Orexins are excitatory neuropeptides generated from the prepro-orexin precursor that is exclusively localised in cells of the lateral and posterior hypothalamic region. Orexins are also widely expressed in human and mammalian retinas, such as bipolar cells, amacrine cells and ganglion cells.Orexin-A activates the orphan G-protein-coupled orexin receptor, type 1 (OX1R) and 2 (OX2R). There are approximately 10,000-20,000 orexinergic neurons in the human brain.</p>

<p>The Histone H2A residues 1 to 20 are derived from histone 2A (H2A) which is one of the four core histones (H2A, H2B, H3 and H4) fundamental in compacting eukaryotic DNA into a structure known as the nucleosome. The nucleosome arises when 147 base pairs of DNA wrap around a H3-H4 tetramer and two H2A-H2B dimers, forming the histone octamer core.At the site of DNA entry on the outer nucleosome, the C-terminus of H2A is present and is able to interact with linker histones or other factors. This allows for variation and changes in nucleosome stability to occur. Furthermore Histone H2A has histone variants such as H2A.Z and H2A.X (which are present in all organisms) and these variants alter the organisation of the DNA.Due to histones containing a large number of lysine and arginine residues they have a positive net charge which interacts in an electrostatic manner with the negatively charged phosphate groups in DNA. The transcriptional activation or silencing of the chromatin is controlled by ATP-dependent chromatin remodelling factors and histone modifying enzymes which target histone proteins. Both processes function to alter to change the positioning of the nucleosome, allowing the DNA it to be either available to the transcription machinery or inaccessible.Biotin has been added to the lysine on GGK.</p>

<p>H1 is the linker histone and is important for chromatin condensation, it binds to the nucleosomal core particles and protects the free linker DNA (ˆ¼20 bp) between each nucleosome. H1 can fine-tune transcription in a locus-specific manner. H1 is involved in several processes, its interaction partners include: pre-mRNA splicing factors- histone chaperones- components of the transcription machinery and DNA-damage response factors. There a 12 subtypes of the H1 linker histone, and they are thought to have specific functions, making H1 the most divergent histone protein family. Like other histones, H1's are extensively post-translationally modified with modifications including: methylation, acetylation, ubiquitination, formylation, poly-ADP ribosylation and phosphorylation.Changes in H1 composition and expression levels are seen in several cancers and other diseases.</p>

<p>Histone H3 (1-20) K4Me3, K9Ac-GG-[Lys(5-FAM)] is derived from Histone 3 (H3) which is one of the four core histones fundamental for compacting eukaryotic DNA into the nucleosome.-Lysine 4 of Histone H3 (1-20) K4Me3, K9Ac-GG-[Lys(5-FAM)] has been tri-methylated, lysine 9 has been acetylated and the C-terminal has been labelled with 5-Carboxyfluorescein (5-FAM), a widely used green, fluorescent tag. Additionally, this peptide contains an uncharged C-terminal amide.LD: Histone H3 (1-20) K4Me3, K9Ac-GG-[Lys(5-FAM)] is derived from Histone 3 (H3) which is one of the four core histones (H2A, H2B, H3 and H4) fundamental in compacting eukaryotic DNA into the nucleosome. The nucleosome arises when 147 base pairs of DNA wrap around a H3-H4 tetramer and two H2A-H2B dimers, forming the histone octamer core. Both H4 and H3 are highly conserved and perform roles in binding to segments of DNA which enter and leave the nucleosome and in chromatin formation. Similar to the other core histone, H3 has a globular domain and a flexible N-terminal domain, 'histone tail' which can undergo modifications such as acetylation, methylation, phosphorylation and ubiquitination. Due to histones containing a large number of lysine and arginine residues they have a positive net charge which interacts in an electrostatic manner with the negatively charged phosphate groups in DNA. The transcriptional activation or silencing of the chromatin is controlled by ATP-dependent chromatin remodelling factors and histone modifying enzymes which target histone proteins. Both processes function to alter the positioning of the nucleosome, allowing the DNA it to be either available or inaccessible to the transcription machinery.The lysine at position 4 of this peptide has been tri-methylated and it is implicated in studies that this modification may remodel the chromatin so that it is more accessible to transcription factors, which may ultimately increase the level of gene expression. The lysine at position 9 has been acetylated, which neutralizes the positive charge on the amino acid, loosening the chromatin structure. This alteration to the accessibility of chromatin promotes the initiation of transcription.Additionally, Histone H3 (1-20) K4Me3, K9Ac-GG-[Lys(5-FAM)] has a C-terminal GKK linker labelled with 5-Carboxyfluorescein (5-FAM), a widely used green fluorescent tag. This peptide also has an uncharged C-terminal amide.</p>

<p>Gag peptide, derived from the simian immunodeficiency virus (SIV), is a homologue of the human immunodeficiency virus (HIV) gag protein which interacts with viral components in order to induce the infectious form of the virus. SIV can be used to model HIV.</p>

<p>Apidaecin IB was isolated from the honeybee Apis mellifera. As a cationic proline-rich antimicrobial peptide (PrAMP), Apidaecin IB shows sequence homology with drosocin but is devoid of any pore-forming activity. Apidaecin IB is most active against gram-negative bacteria, it can navigate the outer membrane to the periplasm and then to the cytoplasm. Apidaecin IB is a non-lytic AMP, the main target of its antimicrobial activity appears to be inhibition of the chaperone heat shock protein DnaK. Toxicity appears to be exclusively to bacteria and thus has been trialled as a treatment for systemic bacterial infections. Numerous analogues and derivatives are being investigated to establish Apidaecin IB mode of action and also to improve its functionality.</p>

<p>Human adrenocorticotropic hormone (ACTH), also known as corticotropin, is a tropic hormone produced and secreted by the anterior pituitary gland and member of the melanocortins peptide family. ACTH is cleaved from the precursor proopiomelanocortin (POMC). ACTH is an important component of the hypothalamic-pituitary-adrenal (HPA) axis and is often produced in response to biological stress. ACTH acts to increase the production and release of cortisol via its interaction with the ACTH receptor- ACTHR, also known as melanocortin type 2 receptor (MC2R). Receptor activation increases the intracellular concentration of cAMP via adenylyl cyclase.Abnormal ACTH levels in the body has been linked to primary adrenal insufficiency/Addison's disease, Cushing's disease and secondary adrenal insufficiency. ACTH (15-24) has been shown to be a competitive ACTH receptor antagonist and can be used as a method to combat the overproduction of cortisol. Treatment with ACTH (15-24) inhibits activation of a specific melanocortin 2 receptor (MC2R) by inhibiting adrenocorticotropin hormone (ACTH)-induced production of cortisol. ACTH (15-24) is provided here with a C-terminal cysteine residue for conjugation reactions.</p>

<p>Nociceptin is a potent anti-analgesic, effectively counteracting the effect of pain-relievers. A neuropeptide that modulates nociception, it acts by binding the nociceptin receptor (NOP). Nociceptin does not bind to μ, θ´, or K opioid receptors and thus lacks the addictive potential. Administration of nociceptin leads to sensations of pain and is associated with memory, learning, eating, and anxiety.</p>

<p>The coronavirus (CoV) nucleoprotein is the major component of CoV structural proteins. Also known as the nucleocapsid protein, it is an abundant RNA-binding protein critical for viral genome packaging. These factors make nucleoprotein a good target for developing new antiviral drugs. In addition, the identification of epitopes within the nucleoprotein sequence can help design more effective SARS-CoV-2 vaccines.Models have predicted epitopes exhibiting antigenicity, stability and interactions with MHC class-I and class-II molecules. Nucleoprotein (56-70) is an epitope candidate with various HLA restrictions. This epitope can be used to better vaccine design for more durable CD4+ and CD8+ T cell responses for long-lasting immunity.</p>

<p>C-terminal telopeptide is produced when type I collagen in the bone is degraded and so released into the blood. Within collagen structure, made up of a triple helix of 3 amino acid chains, C-telopeptide is located at the C-terminus, and at the N-terminus there is an N-telopeptide. Both the N and the C-telopeptides are involved in the formation of collagen enzymatic cross links which are crucial for Collagen properties in the connective tissues of the body such as the bone and skin. Collagen properties allow connective tissues to be strong, stiff and maintain their structural integrity. Furthermore collagen acts as a scaffold for other extracellular matrix proteins.Due to the presence of C-telopeptide in the blood following the degradation of type 1 collagen, C-telopeptide can be used to monitor the progression of bone diseases where the pathogenesis commonly involves bone degradation.</p>

<p>The coronavirus (CoV) nucleoprotein is the major component of CoV structural proteins. The nucleoprotein has a critical role in virus assembly and RNA transcription. The nucleoprotein is essential in the formation of helical ribonucleoproteins and in regulating viral RNA synthesis. The nucleoprotein can also regulate infected host cellular mechanisms. It is highly expressed during infection and may induce protective immune responses against SARS-CoV and SARS-CoV-2.The nucleoprotein residues DKDPNFKDQVILLNK (341-355) from SARS-CoV-2 have been identified as a T-cell epitope with a predicted HLA restriction. Immune targeting of confirmed epitopes may potentially offer protection against SARS-CoV-2 and help the development of vaccines for long-lasting immunity.</p>

<p>Fragment 498-514 of the BCL6-interacting co-repressor (BCoR) C-terminally labelled with biotin.</p>

<p>Teduglutide is a GLP-2 analogue, in which the alanine at position 2 has been substituted with glycine making the peptide resistant to degradation by dipeptidyl peptidase-4 (DPP-4)- Teduglutide therefore has a longer half-life than GLP-2 (2-3 hours for teduglutide vs 7 min for GLP-2). Teduglutide has high bioavailability after subcutaneous administration, suggesting that teduglutide has enhanced biological activity, relative to native GLP-2.GLP-2 is a gut hormone produced in the enteroendocrine L cells of gastrointestinal tract by the cleavage of the 160-amino-acid proglucagon molecule. GLP-2 is secreted following the ingestion of food and carries out its activities via the GLP-2 G-protein coupled receptors (GLP-2Rs). GLP-2 has a range of roles within the cell, including: anti-inflammatory effects- promoting the expansion of the intestinal mucosa- stimulating intestinal blood flow- inhibiting gastric acid secretion and gastric emptying- increasing intestinal barrier function and enhancing nutrient and fluid absorption.</p>

<p>LRRKtide (also called moesin) is a peptide substrate for leucine-rich repeat kinase 2 (LRRK2). The sequence of LRRKtide has been derived from the ERM proteins: Ezrin (amino acids 561-573), radixin (amino acids 558-570) and moesin (amino acids 539-553). These proteins influence cytoskeletal dynamics by anchoring the cytoskeleton to the plasma membrane. LRRK2 phosphorylates LRRKtide at its Thr558 site.LRRK2 is a large, ubiquitous protein of unknown function. LRRK2 has GTPase and kinase activity, and is located in multiple areas of the cell where it is found associated with intracellular membranes and vesicular structures. Its multiple cellular locations suggest that LRRK2 may be involved in several cellular pathways. LRRK2 is also found in most organs and mutations in LRRK2 have been identified in Parkinson's disease.This peptides has a non-amidated C-terminal end.</p>

<p>Venom peptidomes and proteomes have the potential for significant inroads to novel drug discovery. The non-disulphide bridge peptides (NDBPs) have become a particular focus due to their large range of apparent structures as well biological activity while retaining high specificity.Within the peptidome AcrAP2 was identified in the NDBP as having antimicrobial and bactericidal activity. The nascent peptide contains a predicted hydrophobic region, this was altered to lysine residues generating a hydrophilic region, AcrAP1a. This cationic enhancement markedly increases their antibacterial potency against bacteria and yeast. Furthermore, at all concentrations it inhibited proliferation of the cancer cell lines tested. The duality of AcrAP2a on growth modulation in cancer cell lines as well as having potent antimicrobial activity suggests it is a useful analogue for further research in bacteria and eukaryotes.</p>

<p>Cyclin-dependent kinases (CDKs) are a family of kinases that regulate the cell cycle and gene transcription. Cyclin-dependent kinase 7 (CDK7) forms a trimeric complex with cyclin H and MAT1, which functions as a Cdk-activating kinase (CAK) and promotes cell cycle progression. CDK7 is an essential component of the transcription factor TFIIH, involved in DNA repair. CDK7 is also implicated in mRNA processing, transcription activation, pause induction, and pause release.Cyclin-dependent kinases play key roles in cancer development and metastasis. CDK7 is over expressed in many types of cancer such as breast cancer and renal cell carcinoma (RCC). High CDK7 expression is often seen in more advanced stage tumours, is associated with poor prognosis and is correlated with poor response to endocrine treatment. This peptide contains an N-terminal biotin tag for simple detection and purification.</p>

<p>Galanin is widely distributed in the central nervous, peripheral, and endocrine systems. Galanin's overarching function is as an inhibitory, hyper-polarizing neuromodulator for classical neurotransmitters like acetylcholine and serotonin. Galanin interacts with 3 receptor subtypes, GalR1-3 G protein-coupled receptors inserted into the plasma membrane. GalR1 is believed to activate a Gβγ pathway to regulate MAPK activation. GalR2 can also activate the MAPK pathway, but unlike GalR1, there is detectable inositol phosphate production. GalR3 is associated with the Galphai/o pathway. Activation of the receptor leads to a cellular influx of K+. Each receptor has been associated with neurological diseases such as GalR3 and epilepsy.Galanin is a key regulator of growth hormone and insulin release and adrenal secretion however the role galanin plays is not clear. Administration of galanin to animal models leads to inhibition of insulin secretion but this is not replicated in humans.N-terminal galanin fragments naturally occur in vivo, but their relevance is unclear. Some N-terminal fragments reduce metabolic and functional disorders in experimental heart damage. Their relative abundance varies, with fragment (13-20) being one of the lowest quantities detected. The physiological relevance of the galanin fragment (13-20) and its affinity to the various Gal receptors has yet to be made clear. Binding assays and displacement assays in rat brain tissue have been performed with similar N-terminal galanin fragments to try and elucidate their function. Using N-terminal fragments such as galanin (13-20) can help clarify the role of full-length galanin in various roles, such as during myocardial ischemia and reperfusion injury. This may highlight new agonists/antagonists for the galanin GalR receptors that can be therapeutic targets.</p>

<p>The crude venom of the wasp Polybia paulista consists of 30% polybia-MPII. Polybia-MPII is a mastoparan, it is rapidly distributed around the organism point of inoculation via the circulation. As a secretagogue, polybia-MPII has myotoxic action and minor neurotoxic effects. Polybia-MPII has been injected sub-cutaneously and intra-muscularly into mice for pathology and immunohistochemistry assays.As an antimicrobial agent, polybia-MPII is highly effective, with a lower haemolysis rate compared to other mastoparans. Polybia-MPII also shows considerable anti-fungal activity.</p>

<p>SSG-acid tripeptide consists of two serines and one glycine residue, this was synthesised from the dipeptide L-Seryl-L-glycine- the dipeptide SG-acid is also available in our catalogue. SSG-acid has a net charge of 0, it can act as a Bronsted base by accepting a hydron from a donor thus giving it diverse biological and chemical uses.Glycosylated SSG tripeptide was found to act as a competitive ATPase inhibitor produced by the fungal pathogen Mycosphaerella pinodes, named Supprescin A.</p>

<p>The coronavirus (CoV) nucleoprotein is the major component of CoV structural proteins. The nucleoprotein has a critical role in virus assembly and RNA transcription. The nucleoprotein is essential in the formation of helical ribonucleoproteins and in regulating viral RNA synthesis. The nucleoprotein can also regulate infected host cellular mechanisms. It is highly expressed during infection and may induce protective immune responses against SARS-CoV and SARS-CoV-2.The nucleoprotein residues MSDNGPQNQRNAPRITF (1-17) from SARS-CoV-2 have been identified as a T-cell epitope with a predicted HLA restriction. Immune targeting of confirmed epitopes may potentially offer protection against SARS-CoV-2 and help the development of vaccines for long-lasting immunity.</p>

<p>The SARS-CoV-2 non-structural protein 13 (NSP13) has been identified as a target for anti-viral therapeutics due to its highly conserved sequence and is essential for viral replication.  NSP13 is part of the helicase superfamily 1B. As an NTPase and RNA helicase, NSP13 binds to RNA-dependent RNA polymerase and acts in concert with the replication-transcription complex to stimulate backtracking and further activate NSP13 helicase activity. These factors make NSP13 a good target for developing new antiviral drugs. In addition, the identification of epitopes within the NSP13 sequence can help design more effective SARS-CoV-2 vaccines.Models have predicted epitopes exhibiting antigenicity, stability and interactions with MHC class-I and class-II molecules. NSP13 (421-435) is an epitope candidate with various HLA restrictions. This epitope can be used to better vaccine design for more durable CD4+ and CD8+ T cell responses for long-lasting immunity.</p>

<p>Residues 1-14 of the plasma glycoprotein angiotensinogen (ANG). ANG is a macromolecular precursor of angiotensin I and subsequent angiotensin family members. Angiotensins regulate blood pressure and electrolyte balance. ANG is selectively cleaved by the aspartic protease, renin, to initiate the angiotensin-processing cascade.This region represents the renin cleavage site of ANG, also known as renin substrate.</p>

<p>Amphipathic alpha-helical cationic antimicrobial peptides (AMPs) are rapidly bactericidal and have broad spectrum activity. As AMPs have non-specific modes of action involving membrane disruption, bacteria are less likely to develop resistance to them (unlike traditional antibiotics). KLAL is a model compound to form amphipathic helices that are able to bind to membranes and increase the membrane permeability. KLAL model peptides may also form a β-structure under appropriate conditions. Peptide is labelled with an N-terminal 5-carboxyfluorescein (5-FAM), a widely used green fluorescent tag.</p>

<p>SARS-CoV-2 Spike (976-984)</p>

<p>TAT-Beclin Scrambled is a peptide derived from a region of Beclin 1, which interacts with a newly identified negative regulator of autophagy, GAPR-1 (also called GLIPR2) to act as a potent inducer of autophagy. Autophagy is an essential process that maintains cellular homeostasis and carries out lysosome-mediated degradation of unwanted proteins in the cytoplasm. It is often examined when looking at disease pathways because of this regulatory function. While the immune system initiates the removal of viruses and pathogens through the autophagic pathway, some viruses (such as HIV) are able to evade this process.TAT (47-57) is present due to its properties as a cell penetrating cationic peptide (CPP). It derived from the N-terminus of the Tat protein, which is a trans-activator of the transcription protein present in the human immunodeficiency virus (HIV). As a CPP, TAT (47-57) is able facilitate the delivery of the Beclin scrambled protein across the plasma membrane.This peptide contains a GG linker between the C-terminus of TAT (47-57) and the N-terminus of Beclin 1.</p>

<p>Ara h 6 is one of the major allergenic proteins from peanut (Arachis hypogaea) which contains approximately 13 potential allergenic proteins. Ara h 6 is a member of the 2S albumins (conglutinins) belonging to the prolamin superfamily which also includes Ara h 2. 2S albumins contain major food allergens from seeds of many mono- and dicotyledon plants and share a common compact structure that renders the proteins highly resistant to proteolysis.Ara h 6 contains multiple disulphide-bridged cysteine residues, resulting in a tightly coiled, heat-stable, protease resistant core structure that may be important for allergenicity. In mouse models Ara h 2 and Ara h 6 are the main cause of effector responses such as mast cell degranulation and anaphylaxis.This peptide represents a tryptic peptide of Ara h 6. The phenylalanine residue at position 11 of this peptide is isotopically labelled with carbon-13 (9) and nitrogen-15 (1), giving this peptide a mass increase of 10 compared to the unlabelled peptide.</p>

<p>Somatostatin-14 (SST-14) is a small cyclic peptide hormone secreted by hypothalamus. SST-14 has several roles including inhibiting the release of several hormones such as- growth hormone (GH), gastrin and gastric acid, insulin and glucagon and the regulation of amyloid β-42. In the brain somatostatin increases body temperature and influences visceral functions (e.g. increased blood pressure, decreased heart rate, prevents sympathetically mediated hyperglycemia and stimulates gastric acid secretion).Somatostatin is also present in an N-terminally extended form, somatostatin-28. In mammals, both somatostatin-14 and 28 originate from the prohormone, prosomatostatin, which is generated after removal of a 24 amino acid signal sequence from the 116 amino acids precursor, preprosomatostatin. Somatostatin-14 and 28 bind with similar affinity to five distinct somatostatin receptor subtypes, sst1 to sst5. These receptors belong to the G-protein coupled seven transmembrane domain receptor family and are related to the urotensin II receptors.</p>

<p>CREB327/active transcription factor CREB-A (113-126) Biotinyl, human.</p>

<p>Magainins, also known as PGS (peptide glycine serine) are anti-microbial peptides originally isolated from the skin of the African clawed frog Xenopus laevis, they belong to a large family of amphibian amphipathic alpha-helical cationic anti-microbial peptides (CAMPs). Magainin II is active against a wide spectrum of pathogens including Gram-positive and Gram-negative bacteria, fungi and protozoa and has anti-viral properties. Magainins also displays anti-tumour activities and are known to facilitate wound closure and to reduce inflammation.Magainin peptides act by first binding to and then causing eventual collapse of the membrane. Magainins, carry several positive charges, and interact best with membranes with a negative surface charge, such as bacteria or tumour cells. They are non-toxic to healthy eukaryotic cells which are charge-neutral at their outer membrane. The physical mode of action of these peptides reduces the ability of target organisms to develop resistance to them, suggesting good therapeutic potential.</p>

<p>Identification of cell penetrating conjugates has aided numerous areas of scientific development. The Drosophila transcription factor Antennapedia contains a homeodomain that can be internalised by cells to the cytoplasm and to the nucleus in a receptor-independent mechanism. The key residues for internalisation have been sequenced (RQIKIWFQNRRMKWKK), named penetratin, and used in several studies to aid entry of fusion proteins into cells.The full 60 amino acid homeodomain was fused to a T cell epitope of the influenza nucleoprotein and successfully internalised into T cells for presentation. The fragment known as penetratin was fused to a ligand for Grb-2 resulting in inhibition of downstream Grb-2 signalling events. Penetratin has also been used in vivo to prime cytotoxic T lymphocytes by conjugating short antigenic peptides to the CPP. Penetratin is provided here as a C-terminal amide with a C-terminal 5-carboxyfluorescein (5-FAM), a widely used green fluorescent tag often preferred over FITC due to its high stability- absorbance 492 (nm), 518 emission (nm).</p>

<p>DNA damage-binding protein 2 is able to recognise and bind to UV-induced DNA lesions and facilitates efficient recognition by XPC. DDB2 and XPC then initiate global genome nucleotide excision repair (GG-NER) to protect DNA from mutagenesis associated with premature aging and skin cancer. Timely DDB2 dissociation is required for DNA damage handover to XPC and swift progression of the multi-step repair reaction. Damage handover from DDB2 to XPC coincides with the arrival of the TFIIH complex, which further promotes DDB2 dissociation and formation of a stable XPC-TFIIH damage verification complex. DDB2 binds directly to and flips out UV-induced damaged bases to create a more suitable substrate for XPC.The UV-DDB complex is part of a larger E3 ubiquitin-ligase complex (CRL4DDB2), also containing CUL4A, RBX1, and the COP9 signalosome. AF647 dye is a commonly used bright, far-red-fluorescent dye which is pH-insensitive over a wide molar range.</p>

<p>[5-FAM]-Val.</p>

<p>Venom peptidomes and proteomes have yielded significant novel drug discoveries. The non-disulphide bridge peptides (NDBPs) have become a particular focus due to their large range of structures as well as biological activity while retaining high specificity.In scorpion venom A. crassicauda, AcrAP1 was identified as a NDBP. Data shows it has antimicrobial activity against bacteria and yeast while also capable of haemolysing of horse erythrocytes. However, AcrAP1 did not affect the growth of the cancerous cell lines tested. Therefore, this peptide could be a useful model for modification to improve its potency. Furthermore, it may allow researchers to identify specific targets in disease pathways for new drug designs. A significant example of this, bradykinin-potentiating peptide Captopril® manages hypertension and originated from the conserved NDBP family.</p>

<p>Fluorogenic substrate peptide of the 20S proteasome. In its intact state this peptide is non-fluorescent, however when aminomethylcoumarin (AMC) is released upon hydrolysation, fluorescence can be detected. This peptide is therefore a useful tool for analysing the activity of the 20S proteasome as well as other chymotrypsin-like proteases and calpains. This peptide is also a substrate for chymase, papain, carboxypeptidase Y, proteinase yscE (kexin) and ingensin.AMC is a fluorescent dye with excitation maxima at around 360 nm and emission maxima at around 450 nm. AMC can be excited with a mercury lamp and observed using a UV filter set.</p>

<p>Tat (47-57) is a cell penetrating cationic peptide derived from the N-terminus of the Tat protein, which is a trans-activator of the transcription protein present in the human immunodeficiency virus (HIV). Specifically TAT (47-57) is located within the arginine-rich basic domain 48-60 of the TAT peptide which as a whole has three domains which function to aid HIV through transactivation, DNA binding and nuclear transport. As a cell penetrating peptide (CPP) TAT aids in the cellular uptake of molecules and hence serves a valuable purpose in transduction methods. This property has been demonstrated through its ability of allowing toxins such as the neurotoxin Botulinum neurotoxin Type A, produced by the Clostridium botulinum type A bacteria to penetrate the skin barrier non-invasively. Additionally TAT (47-57) can be used to deliver proteins, fluorophores, chelators and DNA to target cells.</p>

<p>Amino acids 1-15 of β-amyloid protein (Aβ), this fragment represents one of many short Aβ species found in vivo and is formed by the cleavage of amyloid β precursor protein by β- and α-secretase.Aβ has been identified as the key subunit of the extracellular plaques found in the brains of patients with Alzheimer disease (AD) and Down syndrome (DS). Aβ has therefore been extensively studied as a potential target for treatment of AD.Aβ is formed from the cleavage of the large, transmembrane protein- APP (amyloid precursor protein). Cleavage of APP by β- and then γ-secretases results in the formation of Aβ. Aβ can aggregate to produce amyloid-β oligomers, which are thought to be highly neurotoxic. Over time Aβ can further aggregate to produce the characteristic senile plaques present in AD and DS. Aβ can be degraded by enzymes such as neprilysin, insulin degrading enzyme or endothelin converting enzyme. At physiological levels Aβ may be involved in controlling synaptic activity and neuronal survival.</p>

<p>A20FMDV2, a peptide derived from the foot and mouth disease virus, inhibits the epithelial-specific integrin alphavβ6 and here is labelled with 4-fluorobenzoyl as the light version of the PET ligand 4-[18F]Fluorobenzoyl A20FMDV2 which can be used for in vivo imaging.</p>

<p>The AH1 peptide is a H2-Ld-restricted epitope derived from the sequence of the gp70 envelope protein of the ecotropic mammalian C-type retrovirus, murine leukaemia virus (MuLV, emv-1).The envelope gene products of MuLV are expressed in a variety of tumour cells, including B16 melanoma, lymphomas and leukaemia's. AH1 peptide is a tumour-associated antigen and is highly expressed on CT26 and C51 tumour cells.</p>

<p>AAT is a highly abundant serine protease inhibitor primarily produced in the liver to protect the lung tissue. However, misfolding of AAT can result in significant liver disease, lung disease, and cancers. Defective AAT is characteristic of the misfolding protein diseases known as serpinopathies.Ion mobility mass spectrometry (IM-MS) was used to identify Ac-TTAI-amide as a ligand effecting α1-antitrypsin stability. Interaction of Ac-TTAI-amide with AAT results in increased stability and reduced polymerisation. Thus Ac-TTAI-amide is a useful target for further research in to serpinopathy management.</p>

<p>EB1 is a penetratin analogue that was synthesised to be an endosomolytic cell penetrating peptide (CPP). Certain amino acids in the penetratin sequence were replaced with histidine to encourage formation of an alpha helix upon protonation in the acidic endosomes. As a CPP, EB1 has been shown to form a strong interaction with the phospholipid bilayer during insertion with rapid cellular uptake, there is a moderate amount of cell leakage and no significant cytotoxicity. EB1 is provided here as a C-terminal amide with a N-terminal 5-carboxyfluorescein (5-FAM), a widely used green fluorescent tag often preferred due to its high stability absorbance 492 (nm), 518 emission (nm).</p>

<p>HLA-A*02 is a class I major histocompatibility complex (MHC) allele which is part of the HLA-A group of human major histocompatibility complex (MHC) leukocyte antigens (HLA), found at the HLA-A locus. HLA-A is one of three major types of human MHC class I cell surface receptors. The receptor is a heterodimer, and is composed of a heavy alpha chain and smaller β chain. MHC Class I molecules such as HLA-A are part of a process that presents short polypeptides to the immune system. These polypeptides are typically 7-11 amino acids in length and originate from proteins being expressed by the cell. Cytotoxic T cells in the blood "read" the peptide presented by the complex and should only bind to non-self peptides. If binding occurs, a series of events is initiated culminating in cell death via apoptosis. This peptide corresponds to the Hepatitis B variant (HBV) core sequence which is presented on the MHC class I antigen HLA-A*02 and contains fluorescein, a widely used flourescent dye.</p>

<p>This is an incretin hormone that causes glucose dependent release of insulin by pancreatic beta cells. It is the cleavage product of GLP-1 (1-36) amide peptide.  This peptide, human GLP-1 (7–36), shares the same sequence with preproglucagon (78-107), amide, human.</p>

<p>Histatins are histidine rich cationic peptides produced in salivary glands and released into the saliva. The main histatins that make up more than 80% of histatins in saliva are histatin 1, histatin 3 and histatin 5. There are two histatin genes, one which encodes histatin 1, and one that encodes histatin 3, all other histatins are derivatives of these two histatins. Histatin 3 is a precursor of histatin 5, each with distinct roles.Histatin 5  is considered an antimicrobial peptide (AMP) as it has antibacterial activity as has been shown against opportunist infections such as P. aeruginosa, E. coli, and S. aureus. Histatin 5 also has potent anticandidal activity for example against Candida and Leishmania, it is shown to be the strongest antifungal of the histatins.  The antifungal activity functions by invasion of the microbe and entry to the mitochondria, histatin 5 then inhibits ATPase activity resulting in rapid depletion and ultimately bacterial cell death/apoptosis. As a salivary peptide, it inhibits Bacteroides gingivalis proteinase clostripain and protease activity microbe implicated in periodontal disease.</p>

H-Glu[Cyclo(Arg-Gly-Asp-D-Tyr-Lys)]2 is a cyclic peptide that contains the sequence of amino acids Arg, Gly, Asp, D, Tyr and Lys. It is a peptide macrocycle that has been shown to be effective against tumor cells. This peptide has been derivatized for targeting purposes and has been shown to be an effective imaging agent for tumor cells in vivo. H-Glu[Cyclo(Arg-Gly-Asp-D-Tyr-Lys)]2 is also biochemically active and can inhibit the growth of cancer cells through multiple mechanisms.

<p>Cell penetrating peptides (CPP) are a useful tool for drug delivery, but their cell-specific uptake is still being improved. Work with the model amphipathic peptide (MAP) has been important in this field. CPP MAP is an amphipathic α-helix and has been well characterised for its ability to spontaneously permeate the cell membrane by interacting with the lipid bilayer. As a CPP, MAP causes increased membrane permeability and a degree of cell leakage. MAP is being extensively studied to optimise drug delivery in numerous cell lines with the target of creating a viable clinical method. Interestingly, the CPP function of MAP also provides it with bactericidal properties by effecting the membrane permeability. MAP is a potent antimicrobial peptide (AMP) against gram negative Neisseria meningitidis, the pathogen of meningococcal disease.MAP is provided here with a N-terminal alkyne attachment. Two of the most regularly encountered functional groups for click chemistry are azides and alkynes, and the azide-alkyne cycloaddition has become the most popular click reaction. The use of click chemistry with alkyne-MAP allows a wide variety of applications particularly for conjugation, modification, and peptide design.</p>

<p>There are three members of the p160 family of steroid receptor coactivators, SRC-1, SRC-2, and SRC-3. These steroid receptor coactivators control the functional output of numerous genetic programs and serve as pleiotropic rheostats for diverse physiological processes. Coactivator proteins interact with nuclear receptors in a ligand-dependent manner and augment transcription.</p>

<p>Palmitoyl KTTKS pentapeptide.</p>

<p>An angiotensin II (Ang-II) receptor antagonist, the sequence of the angiotensin II anti-peptide has been derived from the anti-sense mRNA complementary to the human Ang-II mRNA. The anti-peptide shares 50% sequence homology with Ang-II and acts to inhibit some of Ang-II's biological activities.Ang-II is a key signalling peptide of the renin angiotensin system (RAS), which is involved in regulating blood pressure, cardiovascular function and energy balance. RAS activity is elevated in obesity and is widely studied in relation to lifestyle-related diseases. Ang-II is produced from angiotensinogen (AGT) via the intermediate angiotensin I (Ang-I). AGTis cleaved by the aspartyl-protease, renin, to produce Ang-I, which is then cleaved by the dicarboxyl-peptidase angiotensin converting enzyme (ACE). ACE removes a histidine and a leucine, from the C-terminus of Ang-I to form Ang-II.Ang-II exerts its affect by binding to the G-protein-coupled receptors- Ang II type 1 (AT1) and Ang II type 2 (AT2) receptors. Ang-II plays central roles in glucose metabolism and blood pressure. Increased levels of Ang-II have also been associated with Alzheimer's disease, and certain cancers including oesophageal squamous cell carcinoma (ESCC), brain cancers and breast cancer. The effects of Ang-II appear to be supressed by another branch of the RAS- the ACE2/Ang-(1-7)/Mas pathway.</p>

<p>Biotin-Tat (47-57) is a cell penetrating cationic peptide derived from the N-terminus of the Tat protein, which is a trans-activator of the transcription protein present in the human immunodeficiency virus (HIV). Specifically Biotin-TAT (47-57) is located within the arginine-rich basic domain 48-60 of the TAT peptide which as a whole has three domains which function to aid HIV through transactivation, DNA binding and nuclear transport. As a cell penetrating peptide (CPP) TAT aids in the cellular uptake of molecules and hence serves a valuable purpose in transduction methods. This property has been demonstrated through its ability of allowing toxins such as the neurotoxin Botulinum neurotoxin Type A, produced by the Clostridium botulinum type A bacteria to penetrate the skin barrier non-invasively. Additionally, Biotin-TAT (47-57) can be used to deliver proteins, fluorophores, chelators and DNA to target cells.This peptide contains a covalently bonded N-terminal Biotin tag that can be used for detection and purification.</p>