Peptides

EGFR (963-975)

<p>Histatins are histidine rich cationic peptides produced in salivary glands and released into the saliva and have strong antifungal activity. The main histatins that make up more than 80% of histatins in saliva are histatin-1, histatin-3 and histatin-5. There are two histatins genes, one which encodes histatin-1, and one that encodes histatin-3, all other histatins are derivatives of these two histatins. Histatin-8 is a cleavage product of histatins-3 corresponding to part of its central region.</p>

<p>The SARS-CoV-2 spike protein is present on the outside of the virus particles and can bind to angiotensin-converting enzyme II (ACE2) present on the host cells. The C-terminal receptor binding domain (RBD) of the spike protein binds to the N-terminal peptidase M2 domain of ACE2. This receptor binding results in the internalisation of the virus-receptor complex and is, therefore the mechanism of entry of SARS-CoV-2 into host cells.The spike protein residues IDRLITGRLQSLQTY (975-989) from C 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>Blocks the activity of TGFβ1 in vitro, as measured by its capacity to restore growth of Mv-1-Lu cells in the presence of added TGFβ1. Inhibits TGFβ1-dependent expression of collagen type I mRNA in the liver of mice orally insulted with CCl4.</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>Palmitoyl KTTKS pentapeptide.</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>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>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>

<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>

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>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>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>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>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>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>

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>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>IRBP (161-180) derived from the interphotoreceptor retinoid-binding protein (IRBP), present in the interphotoreceptor matrix and is expressed by cone and rod photoreceptors in the eye. IRBP is involved in retinoid delivery and protects retinal cells from oxidative stress.In retinitis pigmentosa patients, IRBP can be subjected to mutations resulting in a non-secreted form of IRBP to be produced. Furthermore IRBP gene mutations have been associated with high myopia and retinal dystrophy.The expression of IRBP is reduced in diabetes patients which may lead to visual cycle misfunction and the photoreceptors can be vulnerable to damage.</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 (466-480) is an epitope candidate with various predicted 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>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 biological activity while retaining high specificity.AcrAP2 was identified as a NDBP in A. crassicauda within highly conserved family of proteins. Data shows it has antimicrobial activity against bacteria and yeast while also capable of haemolysing horse erythrocytes. However, AcrAP2 did not affect the growth of 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>Sal-like4 (SALL4) derived peptide able to antagonise the SALL4-NuRD complex in hepatocellular carcinoma, turning SALL4 from a dual transcription repressor-activator to a singular transcription activator. Displays antitumour effects in xenograft mouse models.</p>

<p>TMPRSS4 (199-207) fluorogenic peptide</p>

<p>Small peptide design has become of interest to catalyse chemical transformations within the cell. The aim is to generate peptides to enhance the hybridization of attached oligonucleotides to complementary DNA sequences. (AAKK)4 is modelled on the surface of staphylococcal nuclease, it a short cationic lysine-rich peptide that can deliver a nucleophile to DNA or RNA. (AAKK)4 peptide can improve DNA-PNA (peptide nucleic acid) hybridisations dramatically as well as increase strand invasion rate. (AAKK)4 peptide is a non-lipid approach for cell penetration which is preferable for certain cell lines due to cytotoxicity issues. (AAKK)4-antisense conjugates have been used to silence gene expression.(AAKK)4 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-(AAKK)4 allows a wide variety of applications particularly for conjugation, modification, and peptide design.</p>

<p>SARS-CoV-2 NSP7 (1-15)</p>

<p>Bradykinins and their associated kinins are inflammatory mediators produced during inflammation. The two main kinins in mammals are the nonapeptide bradykinin, BK (1-9) and the decapeptide kallidin (KD), [Lys0]-BK(1-10). Their biological actions are mediated by two distinct receptors, termed B1 and B2.-BK is involved in several pathophysiological processes, such as inflammation, pain, cell proliferation, and tumours. It plays a crucial role in corneal epithelial cells, corneal stromal cells, and fibroblasts.Inflammation has been reported as one significant hallmark of breast cancer in relation to tumour development, metastasis, and invasion. The bradykinin receptor 1 (B1R) associated with kallidin is highly expressed on inflammatory breast tumour cells thus providing a promising targeting site for tumour recognition and sufficient receptor mediated endocytosis.</p>

<p>Histone H3 (1-21) K9Me2 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 (1-21) lysine 9 has been dimethylated.</p>

<p>Peptide derived from the myosin heavy-chain (MyHC) proteins which are differentially expressed in mammalian skeletal muscles.</p>

<p>[5-FAM]-TAT 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.It contains 5-carboxyfluorescein (5-FAM), a widely used green fluorescent tag.</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>The LDVP peptide (CS1), located in the type III connecting segment (V-region) of fibronectin, exhibits cell binding properties thus contributing to the adhesion of fibronectin to other cells.</p>

<p>Proinsulin connecting peptide (C-peptide), links the A and B chains of proinsulin. Upon enzymatic cleavage of C-peptide from pro-insulin in the pancreas, C-peptide is released into the blood stream along with insulin (A- and B-chains bonded together) in equimolar quantities. C-peptide can influence a wide variety of physiological conditions linked to diabetes, such as neuropathy, nephropathy, and encephalopathy. C-peptide is able to ameliorate and reverse the degrading effects of neuropathy in diabetes.</p>

<p>Acetylated α-synuclein (1-7) amide is derived from the alpha-synuclein intrinsically disordered protein which is found in the 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.However it has been found that the 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-b 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.Alpha-synuclein can be subjected to the post-translational modifications of phosphorylation and N-terminal acetylation. When acetylation occurs at the N-terminus of an alpha-synuclein monomer, the intramolecular hydrogen bonds are altered thus reducing the rate of alpha-synuclein aggregation and the strength at which it interacts with the membrane is increased.</p>

<p>Galanin is a widely distributed neuropeptide in the central nervous system (CNS), peripheral regions and endocrine system. Galanin interacts with 3 receptor subtypes, GalR1-3 G protein-coupled receptors inserted into the plasma membrane. Galanin has a role in energy homeostasis. Central injections of galanin to the amygdala led to food intake in rats. Galanin also acts in the CNS to inhibit neurotransmitter release, such as acetylcholine. Galanin has been implicated in numerous neurological conditions, including Alzheimer's disease, depression, and epilepsy. A better understanding of the galinergic signalling pathways may uncover a source for therapeutics for conditions such as epilepsy.Unlike human galanin, full-length porcine galanin contains only 29 amino acids and is C-terminally amidated. The first 15 residues are still highly conserved.  The best-recognized effect of galanin on the endocrine pancreas is the inhibition of insulin secretion in vitro and in vivo on multiple model systems, including rats, dogs, and mice. However, the same effect cannot be achieved at the same concentrations in human models with infusions of porcine galanin. Structural activity and point mutation studies show that the N-terminal (1-15) fragment is vital for the interaction/activation of the GAL receptor and the inhibition of insulin secretion.</p>

<p>Portion of EBV EBNA 3</p>

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

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

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

<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>Flagellin is a structural protein which forms the major portion of bacterial flagellar filaments. The N- and C-terminals of flagellin are highly conserved regions, whereas the central core can vary greatly between bacterial species. Flagellin 22 (flg22) is the stretch of amino acids most conserved across bacterial species and is located towards the N-terminal of the flagellin protein.Flg22 is a potent elicitor of plant immune responses and is recognised in plants by the membrane bound leucine-rich repeat-receptor kinase FLAGELLIN SENSITIVE 2 (FLS2). Flg22 induces defence gene expression to trigger both local and systemic immune responses and is thus widely used in plant defence studies.</p>

<p>EC-acid has a formal charge of 0 and a range of biological and chemical uses. CE-acid is also available in our catalogue.</p>

<p>H3 is a core component of the nucleosome, functioning in DNA compaction and availability to transcription machinery. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodelling. 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. There is a wealth of data recording these modifications but understanding their significance is not as clear. In Caenorhabditis elegans H3K23me3 can be induced by exogenous dsRNA and this modification can persist for four generations after the dsRNA exposure has been stopped. H3K23me3 is enriched in C. elegans heterochromatic regions, the histone methyltransferase SET-32, methylates H3K23 in vitro.A 20-mer fragment of the N terminal histone tail is provided here with threonine 22 phosphorylated and lysine 23 tri-methylated (pT22 K23Me3) with an N terminal biotin label attached. The biotin label should allow for easy use in detection by fluorescence microscopy, ELISA or western blots. Alternatively, it can be purified for protein-protein interactions with the appropriate affinity purification protocol.</p>