Peptides

<p>The [FITC]-Ahx-(KKEEE)3K carrier peptide contains the fluorescent label fluorescein isothiocyanate (FITC), where the isothiocyanate can generate a stable thiourea linkage through reacting with the amine group present on protein molecules. The Ahx group (1,6-aminohexanoic acid) is used as a spacer to N-terminally link the FITC to the (KKEEE)3K carrier peptide. The (KKEEE)3K peptide sequence has shown significant specific renal targeting, thus giving it kidney-specific drug carrier properties. In particular its ability to target drugs to the proximal tubule cells of the kidney suggests potential to aid in the treatment of renal diseases.</p>

<p>Truncated version of SBP1, the fragment of the angiotensin-converting enzyme 2 (ACE2) peptidase domain (PD) α1 helix important for the interaction of ACE2 with the severe acute respiratory syndrome (SARS coronavirus receptor binding domain (SARS-CoV-2-RBD). Unlike SBP1, SBP2 does not associate with the spike RBD protein.This peptide has a covalently bonded N-terminal Biotin tag that can be used for detection and purification and contains a polyethylene glycol spacer (PEG4).</p>

<p>Alpha-synuclein (1-13) is derived from the alpha-synuclein intrinsically disordered protein which is found in neurons and presynaptic terminals. Encoded by the SNCA1/PARK1 gene alpha-synclein is structurally composed of 140 amino acids, making up the three domains: N-terminal membrane binding domain, a hydrophobic non-amyloid-β component domain and a hydrophilic C-terminal domain. Usually alpha-synuclein plays a role in protecting neurons from apoptotic stimuli and is involved in synaptic vesical trafficking.Accumulation of alpha-synuclein aggregates can lead to neurodegenerative diseases such as Parkinson disease, dementia with Lewy bodies and multiple system atrophy. It is further involved in the fibrilisation of amyloid β and tau which play a major role in Alzheimer disease. Amyloid fibrils are formed from alpha synuclein monomers within the cytosol and when bound to membranes these monomers can undergo conformational changes to form protofibrils and then ring like oligomers. This can result in the formation of transmembrane pores which disrupts the membrane, calcium homeostasis and signalling.In familial Parkinson disease the SNCA1 gene, can be subjected to point mutations such as A30P, E46K and A53T, or over expression. These can result in the increased aggregation of alpha-synuclein.</p>

<p>1D,6L-Lanthionine vasopressin</p>

<p>SCO-spondin is a large multi-domain glycoprotein of the extracellular matrix, widely distributed in the central nervous system (CNS). SCO-spondin is expressed and secreted in early development by the subcommissural organ (SCO), an ependymal differentiation of the brain. SCO-spondin is part of the Reissner's fiber (RF), a thread-like structure in the spinal cord and is involved in axonal pathfinding, development of brain commissural fibres and spinal cord regeneration in vertebrates. SCO-spondin also interferes with several developmental processes including: neuronal development- axonal pathfinding- neuronal survival- neurite extension- neuronal aggregation, and fasciculation.SCO-spondin has several conserved domains, including 26 thrombospondin type 1 repeats (TSR), nine low-density lipoprotein receptor (LDLr) type A domains, two epidermal growth factor (EGF)-like domains, and N- and C-terminal von Willebrand factor (vWF) cysteine-rich domains. The TSR motifs are highly important in many of SCO-spondins neuronal responses.NX210 corresponds to part of the SCO-spondin TSR sequence, it can increase adhesivity and neuritic outgrowth and is involved in cell-cell and cell-matrix interactions. NX210 can increase cell survival and induce neurite outgrowth.</p>

<p>This is a truncated exendin-4 peptide, the original peptide was identified in Gila monster lizard (Heloderma suspectum). Exendin-4 is an incretin mimetic, an analog of glucagon-like-peptide-1 (GLP-1), it stimulates insulin secretion and modulates gastric emptying to slow the entry of ingested sugars into the bloodstream. Exendin-4 is resistant to cleavage by plasma DPP-IV unlike GLP-1. This gives it a longer half-life and duration of action than GLP-1, as well as greater potency in vivo. Exendin-4 increases insulin sensitivity and improves glucose tolerance and is currently used for the treatment of Type 2 diabetes mellitus in its synthetic form Exenatide.Exendin-4 also promotes the production and proliferation of β-cells leading to regeneration of the pancreas. It is a ligand to the exendin receptor and increases pancreatic acinar cell cAMP levels. However, the GLP-1 analog was found to have a toxic effect by inducing hypotension due to relaxation of the cardiac smooth muscle.</p>

<p>Sakamototide is phosphorylated by members of the 5'-adenosine monophosphate-activated protein kinase (AMPK) family of kinases as is therefore ideal for use in kinase assays to test the activity of AMPK family members. The AMPK family includes- salt inducible kinases (SIKs), NUAK's, sucrose non-fermenting (Snf1)-related kinase (SNRK), microtubule affinity regulating kinases (MARKs) and brain specific kinase/BR serine/threonine kinase (BRSK). The kinase activity of AMPK and AMPK-related kinases, is dependent on its phosphorylation at Thr175 by the upstream kinase LKB1 (also known as STK11).</p>

<p>Fibrinogen is a large plasma glycoprotein with a complex structure, and one of the most abundant proteins in blood. Fibrinogen is important in fibrin clot formation, haemostasis, and inflammatory responses. Increased plasma fibrinogen indicates a proinflammatory state and is a risk factor for vascular inflammatory diseases including hypertension and atherosclerosis. Fibrinogen cleavage products act as inflammatory activators in the pathophysiology of allergic asthma.The conversion of monomeric fibrinogen into polymeric fibrin is mediated by thrombin, which binds to fibrinogen and catalyses cleavage of fibrinopeptide A (FpA) and fibrinopeptide B (FpB). Fibrinopeptide B is protected from modifications such as carbamylation by pyroglutamination of the N-terminal amino acid.</p>

<p>Spexin is a neuropeptide that is conserved amongst humans and rodents. Spexin activates galanin2/3 receptors, inducing a different active conformation of GalR2 to galanin. The broad distribution of spexin suggests multiple physiological roles including as a regulating factor in obesity and energy metabolism. Spexin is ubiquitously expressed in human tissue, however, a correlation has been found with obesity and age. Obese patients had significantly lower levels of circulating spexin than those with a healthy weight range. The significance of this suggests spexin regulates appetite, feeding behaviour, and energy expenditure. Spexin also specifically inhibits the uptake of long-chain fatty acids by adipocytes.Spexin is a central modulator of cardiovascular and renal function and can elicit central nervous system behavioural responses. As spexin levels decrease with age there is research to understand if it plays a role in age-related pathophysiology of cardiometabolic conditions. Spexin is also being considered an early biomarker for cardiovascular disease due to the magnitude with which it decreases as the pathophysiology progresses.</p>

<p>Thrombin is the main effector of the coagulation cascade- it is a serine protease. Thrombin binds to active protease activated receptor (PAR) which belongs to a subfamily of G-protein coupled receptors (GPCR). Thrombin activation of mouse PAR-4 reveals an amino terminus sequence of GYPGKF. This is the natural ligand for PAR-4. GYPGKF binds internally to the receptor and leads to signalling activation. Identification of GYPGKF as a PAR-4 agonist has allowed better understand of the function of PAR. Addition of GYPGKF to PAR-4 expressing cell lines achieved 55% of the maximal response of thrombin. GYPGKF can provide understanding of PAR-4 and a template for more potent agonists.</p>

<p>Histone 4 (H4) is one of the four core histones (H2A, H2B, H3 and H4) which are essential for compacting eukaryotic DNA into the nucleosome. Due to the high lysine and arginine content, histones have a net positive charge and therefore electrostatically interact with negatively charged DNA. 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. Like other core histones, H4 has a globular domain and a flexible N-terminal domain, the histone tail, which can undergo modifications such as acetylation, methylation, phosphorylation and ubiquitination.Gene transcriptional activation or inactivation is controlled by ATP-dependent chromatin remodelling factors and histone modifying enzymes. Both processes function to alter the positioning of the nucleosome, allowing the DNA within to be either accessible to the transcription machinery or inaccessible. H4 lysine rich tail plays a role in the higher order chromatin folding.Acetyl-Histone H4 (1-21)-has an uncharged C-terminal amide and is protected from N-terminal modifications by a covalently bonded acetyl group.</p>

<p>Setd8 is a member of the SET domain containing family of proteins and is the sole methyltransferase that catalyses monomethylation of lysine 20 on histone H4 (H4K20me1). This histone modification is involved in regulating DNA replication, chromosome condensation and gene expression.Setd8 is widely expressed and in addition to modifying histone H4, it can modify non-histone proteins, including p53. Setd8 has been shown to play a role in maintaining skin differentiation and is dysregulated in multiple cancer types.</p>

<p>Amyloid β-peptide (Aβ) has been identified as the key subunit of the extracellular plaques found in the brains of patients with Alzheimer's disease (AD) and Down's 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>SMAC/DIABLO [Lys(5-FAM)] is a pro-apoptotic peptide that is derived from the mitochondrial protein known either as Second Mitochondria-Derived Activator of Caspases (Smac) or Direct IAP Binding Protein with low isoelectric point, pI (DIABLO). During apoptosis the mitochondria has increased permeability to Smac/DIABLO, which causes the protein to diffuse into the cytosol. Here, Smac/DIABLO adheres to Inhibitors of apoptosis proteins (IAPs) and prevents them from binding to caspases, which in turn accentuates apoptosis.This peptide has a C-terminal lysine linker labelled with 5-Carboxyfluorescein (5-FAM), a widely used, green fluorescent tag.</p>

<p>A Chemerin-9 peptide derived from chemerin, a protein that is involved in a variety of functions such as autocrine, angiogenic, reproductive and chemotactic processes. Chemerin-9 binds to the chemerin receptor 23 (G-protein coupled receptor) and causes the receptors internalisation.</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. This peptide corresponds to the Hepatitis B variant (HBV) core sequence which is presented on the MHC class I antigen HLA-A*02.</p>

<p>Urumin is a veridical host defence peptide against influenza A virus.The peptide specifically targets the evolutionarily conserved H1 hemagglutinin stalk region of H1-containing influenza A viruses.Urumin has been used against drug-resistant influenza A viruses that are resistant against oseltamivir, zanamivir and peramivir. While its mechanism of action is not fully understood, urumin seems to inhibit viral growth by physically destroying influenza A virions, and is able to protect naive mice from doses of influenza A infection as high as 2 times the LD50. Because of its specific targeting of the hemagglutinin stalk region of the influenza A virus, the mechanism of action of urumin is similar to that of antibodies induced in the body by universal influenza vaccines.</p>

<p>Albumin is a family of globular, water soluble, un-glycosylated proteins commonly found in blood plasma. Albumins generally act as transport proteins that bind to various ligands to transport them around.The most common member of this family is serum albumin. Serum albumin is produced by the liver and is the most abundant plasma protein, it provides oncotic pressure, transports bilirubin, steroids, fatty acids, thyroid hormones and other hormones, and serves as an extracellular antioxidant agent.Too much or too little circulating serum albumin may be harmful. Perturbations in serum albumin concentration is associated with both type 2 diabetes and metabolic syndrome (MetS). Increase in serum albumin concentration might protect against early glycemic deterioration and progression to type 2 diabetes even in subjects without MetS. Albumin in the urine usually denotes the presence of kidney disease.</p>

<p>The HIV gag gene encodes p17 and p24. P17 Gag is a matrix protein that is vital to HIV life cycle, it targets viral RNA to the nucleus and Gag polyproteins to the cell membrane- p17 Gag accumulates in the extracellular space of tissue while interacting with receptors on various cell types to deregulate cell function.During HIV infection the cytotoxic T lymphocyte (CTL) response is key to attenuating viral replication. CTL recognition epitope of p17 Gag is identified as residues 77-85 to activate the immune response. HIV p17 Gag CTL epitope has been used in IgG titres and has been suggested as a suitable prognostic tool for onset of AIDS. A high affinity of IgG for p17 Gag was correlated to patients remaining in an asymptomatic state. p17 Gag epitope has been shown to induce a strong CTL response in the majority of chronically infected HIV patients. This makes the p17 Gag epitope a target for molecular therapy for HIV treatment and potentially a vaccine development.</p>

<p>Histone 4 (H4) is one of the four core histones (H2A, H2B, H3 and H4) which are fundamental in compacting eukaryotic DNA into the nucleosome. Due to the high lysine and arginine content, histones have a net positive charge and therefore electrostatically interact with negatively charged DNA. 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. Like other core histones, H4 has a globular domain and a flexible N-terminal domain, the histone tail, which can undergo modifications such as acetylation, methylation, phosphorylation and ubiquitination.Gene transcriptional activation or inactivation is controlled by ATP-dependent chromatin remodelling factors and histone modifying enzymes. Both processes function to alter the positioning of the nucleosome, allowing the DNA within to be either accessible to the transcription machinery or inaccessible. H4's lysine rich tail plays a role in the higher order chromatin folding.</p>

<p>Ara h 2 is one of the major allergenic proteins from peanut (Arachis hypogaea) which contains approximately 13 potential allergenic proteins.Ara h 2 is a member of the 2S albumins (conglutinins) belonging to the prolamin superfamily which also includes Ara h 6. 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.In mouse models Ara h 2 and Ara h 6 are the main cause of effector responses such as mast cell degranulation and anaphylaxis. Ara h 2 has a high predictive value for diagnosis of clinical peanut allergy and is also more potent than Ara h 1 or Ara h 3 in histamine release assays and skin prick tests.This peptide represents a tryptic peptide of Ara h 2.</p>

<p>ANP (13-26) is derived from the atrial natriuretic peptide (ANP) which is a cardiac hormone involved in maintaining cardio-renal homeostasis. This occurs through the activation of the guanylyl cyclase-coupled receptor, resulting in the increased concentration of cyclic guanylate monophosphate. Moreover its function in the processes of anti-proliferation and anti-angiogenesis allow it to take part in the cardiovascular remodelling process.ANP is a member of the natriuretic peptide family and it is encoded by the NPPA gene, located on chromosome 1. Once synthesized from the 151 amino acid pre-prohormone into its biologically active form, ANP is secreted by the atrial cardiomyocytes in the circulating forms: ANP (1-98) and ANP (99-126). This synthesis process involves the signal peptide being removed from the pre-prohormone resulting in proANP (1-126) which is converted into the circulating forms by the type II transmembrane serine protease Corin.</p>

<p>KR-12-a5 (6-DL).</p>

<p>α-Gliadin (58-73) is derived from Gliadin peptides, the component of wheat involved in the gastrointestinal symptoms of wheat allergy and Celiac Disease (CD). During wheat allergies histamines and leukotrienes are secreted due to gliadin peptide sequences cross-linking two IgE molecules on mast cells and basophils.The glutamine and proline rich peptides of which Gliadin is composed of are resistant to proteolysis during digestion, leaving them active in the gastrointestinal tract. Subsequently these are deamidated by tissue transglutaminase and can bind to HLA-DQ2 or DQ8. As a result in patients with the autoimmune disease CD, there is a Th1-mediated inflammatory immune response against these gliadin peptides.Gliadin can exert additional effects on the intestinal microbiota and ileal barrier function. It has been found that gut microbiota members such as Bifidobacterium and lactobacillus have the ability to digest and inactivate gliadin peptides hence reducing their inflammatory effects in the gastrointestinal system.</p>

<p>Pro B-type natriuretic peptide (Pro-BNP) is secreted from cardiac myocytes and cleaved into BNP and the remaining part of the prohormone N-terminal proBNP (NT-proBNP). When the heart fibres become stretched more BNP and NT-proBNP are released to try and compensate for the increased pressure. During heart failure the walls of the atria become over stretched and thus increase the levels of NT-proBNP detectable. NT-proBNP has a longer half-life than BNP and therefore is detectable at higher levels in blood plasma than BNP. NT-pro-BNP is believed to be cleared by renal excretion, but this is not confirmed. As a diagnostic tool, NT-proBNP (47-76) has become very useful in helping diagnose heart failure and provide a prognosis. The measurement of NT-proBNP (47-76) has been incorporated into management and guidelines of clinical settings. As a research tool it still provides valuable data such as symptoms onset in relation to NT-proBNP levels and how inflammation effects the level of BNP as well as the BNP/ NT-proBNP ratio.</p>

<p>The cyclic pentapeptide cyclo(Arg-Gly-Asp-[D-Phe]-Lys) is a highly potent and selective inhibitor for the alphavβ3 integrin receptor. A related compound, cyclo(Arg-Gly-Asp-[D-Phe]-Val), is a promising anticancer drug candidate- it inhibits angiogenesis and induces apoptosis in vascular cells.Cyclic RGD-containing peptides are selective antagonists of integrins, proteins that play important roles in cell-cell and cell-matrix interactions. In a suitably labelled form, these peptides may serve as useful tools for diagnostic imaging and peptide targeted therapy of some types of cancer.</p>

<p>Histone H3 (1-22) 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 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. 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.</p>

<p>Amino acids 1-17 of human adrenocorticotropic hormone (ACTH). 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.</p>

<p>Portion of HCMV</p>

<p>Histone 4 (H4) is one of the four core histones (H2A, H2B, H3 and H4) which are fundamental in compacting eukaryotic DNA into the nucleosome. Due to the high lysine and arginine content, histones have a net positive charge and therefore electrostatically interact with negatively charged DNA. 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. Like other core histones, H4 has a globular domain and a flexible N-terminal domain, the histone tail, which can undergo modifications such as acetylation, methylation, phosphorylation and ubiquitination.Gene transcriptional activation or inactivation is controlled by ATP-dependent chromatin remodelling factors and histone modifying enzymes. Both processes function to alter the positioning of the nucleosome, allowing the DNA within to be either accessible to the transcription machinery or inaccessible. H4's lysine rich tail plays a role in the higher order chromatin folding.Modifications allow histones to contribute to gene regulation, chromosome condensation and DNA repair. In yeast, methylation of R3 of Histone 4 results in the recruitment of histone acetyl transferase to the chromatin and the acetylation of Histone 4 K5.</p>

<p>Post-transmembrane region (PTM) from the envelope protein (E) of the coronavirus- Mouse Hepatitis Virus (MHV). This protein region is involved in direct membrane binding, with the C-terminal hydrophobic residues of this peptide, thought to be most relevant for membrane binding. After replication, coronaviruses (CoVs) assemble on intracellular membranes, the coronavirus envelope protein (E) is involved in virus assembly and release. E proteins have been located in the endoplasmic reticulum Golgi intermediate compartment (ERGIC) and Golgi of infected cells but are not thought to traffic to the cell surface of infected cells. CoV E is a small hydrophobic protein which is conserved between coronaviruses. E consist of a short hydrophilic amino terminal region, a hydrophobic transmembrane region and a carboxy-terminal region. CoV E protein is an integral membrane protein.E has been considered a therapeutic target for SARS-CoV-2.</p>

<p>LL-13-37 is an active fragment of the LL-37 peptide which has been shown to have anti-fungal properties against Candida albicans.LL-37 is a member of the large cationic family of anti-microbial peptides called cathelicidins which have broad-spectrum anti-microbial activity and are expressed in many species. The only cathelicidin found in humans is LL-37- this is produced in epithelial cells, by proteolytic cleavage from the C-terminal of the hCAP-18 protein. LL-37 can be processed into different forms of anti-microbial peptides. As well as its anti-microbial properties LL-37 also has anti-cancer properties and regulates many aspects of the innate immune system- overexpression of LL-37 has been linked to autoimmune diseases such as asthma and psoriasis.</p>

<p>R9F2 is a specifically designed arginine-rich cell penetrating peptide (CPP) for delivery of antisense molecules (AMOs). Synthetic AMOs are used to interfere with translation and RNA synthesis however their delivery into leukocytes has been an issue. The creation of CPPs such as R9F2 has allowed a new more effective method of delivering AMOs for altering gene expression. The design of the arginine rich peptide with two phenylalanine to the C-terminus allowed better interaction with cell membrane and improved uptake of the cargo. R9F2 has been effectively tested on murine leukocytes to evaluate its efficacy at altering pre-mRNA splicing.R9F2 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-R9F2 allows a wide variety of applications particularly for conjugation, modification, and peptide design.</p>

<p>Portion of EBV BMLF1</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 KEDLKFPRGQGVPIN (61-75) 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>Elabela/Toddler-32  (ELA-32) has been identified as a new endogenous ligand for the apelin G protein coupled receptor (GPCR). Apelin levels have been shown to be reduced in heart failure and pulmonary arterial hypertension (PAH). ELA-32 delivery could be used to supplement the deficit of apelin. It can be cleaved to shorter forms Elabela/Toddler-21, and Elabela/Toddler-11. Apelin and ELA-32 share almost no sequence homology which is unusual for receptor ligands, it suggests a future for apelin receptor biased agonist design.Exogenous administration of ELA-32 to rats has been shown to compensate for the downregulation of apelin seen in PAH. Further research into the potential of this peptide as an endogenous agonist reducing the severity of PAH could provide vital therapeutics in the future for cardiovascular disease.</p>

<p>Duck liver-derived peptide 2 is a novel bioactive peptide with high antioxidant activity. The antioxidant activity is attributed to forming hydrogen bonds between their amino acid residues and free radical molecules. Duck liver-derived peptide 2 increases the activities and mRNA expression levels of intracellular antioxidant enzymes (SOD, CAT, and GSH-Px) in HepG2 oxidative damage cell models. Duck liver-derived peptide 2 can reduce the content of malondialdehyde (MDA) and reactive oxygen species (ROS) accumulation, thereby inhibiting intracellular oxidative damage. Duck liver-derived peptide 2 has the following activity: renin inhibitor, ACE inhibitor, dipeptidyl peptidase IV inhibitor, and antioxidant. This peptide may be used in the research for food-derived bioactive peptides for modified-food development.</p>

<p>Gastric inhibitory polypeptide (GIP) is an inhibiting hormone of the secretin family of hormones. While GIP is a weak inhibitor of gastric acid secretion, its main role is to stimulate insulin secretion - in a glucose-dependent mechanism. Therefore, GIP is referred to as a glucose-dependent insulinotropic peptide. In GIP (Pro 3) the glutamic acid at position 3 has been substituted for a proline.GIP is derived from a 153-amino acid proprotein encoded by the GIP gene and circulates as a biologically active 42-amino acid peptide. It is synthesised by K cells, which are found in the mucosa of the duodenum and the jejunum of the gastrointestinal tract. GIP receptors are seven-transmembrane proteins found on β-cells in the pancreas. These β-cells are those that are able to simultaneously detect glucose and release insulin as a result to GIP binding.The clinical relevance of GIP is related to type 2 diabetes mellitus (T2DM)- studies have found that T2DM diabetics are unresponsive to GIP and have lower levels of GIP secretion after a meal when compared to non-diabetics. In research involving knockout mice, it was found that absence of the GIP receptors correlates with resistance to obesity.</p>

<p>Gastric inhibitory polypeptide (GIP) is an inhibiting hormone of the secretin family of hormones. While GIP is a weak inhibitor of gastric acid secretion, its main role is to stimulate insulin secretion - in a glucose-dependent mechanism. Therefore, GIP is referred to as a glucose-dependent insulinotropic peptide.GIP is derived from a 153-amino acid pro-protein encoded by the GIP gene and circulates as a biologically active 42-amino acid peptide. It is synthesised by K cells, which are found in the mucosa of the duodenum and the jejunum of the gastrointestinal tract. GIP receptors are seven-transmembrane proteins found on β-cells in the pancreas. These β-cells are those that are able to simultaneously detect glucose and release insulin as a result to GIP binding.The clinical relevance of GIP is related to type 2 diabetes mellitus (T2DM)- studies have found that T2DM diabetics are unresponsive to GIP and have lower levels of GIP secretion after a meal when compared to non-diabetics. In research involving knockout mice, it was found that absence of the GIP receptors correlates with resistance to obesity.</p>

<p>N-terminal biotin adrenocorticotropic hormone (ACTH). ACTH, also known as corticotropin, is a cleavage product from a larger precursor proopiomelanocortin (POMC). This 39 amino acid-peptide hormone is produced in the anterior pituitary gland upon stimulation by the corticotropin releasing hormone from the hypothalamus in response to stress. It stimulates the secretion of steroid hormone, specifically glucocorticoids in the adrenal cortex by acting through a cell membrane receptor (ACTH-R). In mammals, the action of ACTH is limited to those areas of the adrenal cortex in which the glucocorticoid hormones cortisol (hydrocortisone) and corticosterone are formed. ACTH has little control over the secretion of aldosterone, the other major steroid hormone from the adrenal cortex.</p>

<p>SGS-acid is a tripeptide consisting of a serine residue followed by a glycine and another serine residue. SGS-acid was synthesised from the dipeptide glycyl-L-serine (GS-acid)- the dipeptide GS-acid is also available in our catalogue. SGS-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.</p>

<p>Tumour progression locus 2 (TPL2) is a mitogen-activated protein kinase kinase (MAP3 K) and is critical for the production of tumour necrosis factor alpha (TNFalpha) in innate immune responses and a potential anti-inflammatory drug target. TPL-2 forms a complex with NF-KB1, p105 and ABIN-2.TPL-2tide is phosphorylated by TPL-2, making TPL-2tide a useful tool for use in kinases assays.</p>

<p>Avi tag is a short 15 amino acid peptide that is capable of biotin modification to the lysine residue without effecting the protein function. The avi tag with biotin is highly specific and stable which makes it an ideal choice for protein interaction studies via purification or detection. Avi tag is more effective than a His tag at protein purification, with these advantages the stabilised version with an N-terminal acetylation is a vital tool in many research fields including drug delivery and DNA-protein interactions.</p>

<p>Part of the angiopep family of peptides which have been derived from the Kunitz domain of human aprotinin. These peptides are able to cross the blood brain barrier (BBB) and have been used to facilitate the delivery of pharmacological agents to the brain, for example to target glioblastoma tumours and recurrent brain metastases of pre-treated breast cancers. Angiopep-2 has higher transcytosis capacity and higher brain volume of distribution than aprotinin. Like aprotinin, angiopep-2 interacts with low-density lipoprotein receptor-related protein 1 (LRP1) which is thought to promote its delivery across the BBB via receptor-mediated transcytosis (RMT). However the interaction with LRP1 may not be the only method for angiopep-2 to cross into the brain.</p>

<p>Albumin (556-564) Bovine is derived from the globular protein Albumin and is found in the blood plasma of humans (known as Human Serum Albumin, HSA) where it serves to maintain plasma pressure and nutritional balance. Another role it carries out is the transportation of bound molecules through the blood. Bovine serum albumin (BSA), composed of 583 amino acids, is very similar to HSA thus allowing BSA to be used as a successful model and a standard protein in laboratory experiments.Although BSA and HAS share homology in their three domains, I, II and III, BSA contains 2 tryptophan whereas HAS only contains 1 tryptophan residue.In agriculture the presence of the albumin protein has been used to assess the health of cows to ensure that a suitable quality of milk and meat are produced. Moreover it is important to detect bovine albumin in food and pharmaceutical products due to it being an allergenic protein.</p>

<p>The blood-brain barrier (BBB) is a major obstacle to drug delivery into the central nervous system (CNS), in particular for macromolecules such as peptides and proteins. However, certain macromolecules can reach the CNS via a receptor-mediated transcytosis (RMT) pathway, and low-density lipoprotein receptor-related protein 1 (LRP1) is one of the promising receptors for RMT. Recent studies have shown that biotinylated L57 binds to LRP1 (CL4)-Fc more efficiently than Angiopep-7 (a different LRP1 ligand), which might explain the improved BBB permeability of L57.</p>

<p>Albumin (51-62) Bovine is derived from the globular protein Albumin and is found in the blood plasma of humans (known as Human Serum Albumin, HSA) where it serves to maintain plasma pressure and nutritional balance. Another role it carries out is the transportation of bound molecules through the blood. Bovine serum albumin (BSA), composed of 583 amino acids, is very similar to HSA thus allowing BSA to be used as a successful model and a standard protein in laboratory experiments.Although BSA and HAS share homology in their three domains, I, II and III, BSA contains 2 tryptophan whereas HAS only contains 1 tryptophan residue.In agriculture the presence of the albumin protein has been used to assess the health of cows to ensure that a suitable quality of milk and meat are produced. Moreover it is important to detect bovine albumin in food and pharmaceutical products due to it being an allergenic protein.</p>

<p>Ova (323-339) is an epitope of interest from egg white albumen, which is widely used in allergy research. Ovalbumin is a glycoprotein that is sufficiently large and complex to be mildly immunogenic. It has been demonstrated that ovalbumin contains B-cell epitopes which are recognized by specific IgE antibodies, and CD4 T cell epitopes restricted by the MHC I-Ad molecule in mice and by HLA-D molecule in human.OVA (323-339) can be used to study binding of class II MHC-peptide and T-cell activation in PBMCs by ELISPOT assays. This method quantifies peptide-epitope specificity and IFN-γ releasing effector cells. It has been shown that OVA (323-339) was responsible for 25-35% of T-cell response of isolated BALB/c mouse. An investigation has demonstrated that OVA and OVA (323-339) induced similar lung inflammation and a Th2-like dominant immune response in mouse model.</p>

<p>β-Amyloid 1-13 (Aβ1-13) is 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. Amyloid β-protein (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 α-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. Biotin is C-terminally linked to the peptide via ethylenediamine for convenient detection and purification. Alternative β-Amyloid fragments and labels are also available, please refer to our peptide catalogue for availability.</p>

<p>Ghrelin is an orexigenic peptide hormone mainly produced in the stomach as precursor preproghrelin. Cleavage of preproghrelin followed by modification leads to the formation of ghrelin with the addition of a fatty acid to its serine 3 residue- ghrelin is capable of activating the growth hormone release receptor (GHSR). Ghrelin is involved in appetite stimulation and growth hormone release.Most circulating ghrelin is in the non-acylated form (des-octanoyl) ghrelin. (Des-octanoyl)-ghrelin has some distinct functions from ghrelin, the lack of acylation prevents binding to the ghrelin receptor and growth hormone release. However, (des-octanoyl) ghrelin has negative inotropic effects on papillary muscle and cardioprotective function. There is evidence (des-octanoyl) ghrelin inhibits proliferation of certain cancer cell lines, while promoting adipogenesis has been observed in other experiments in vivo.</p>