Peptidi

<p>Epitope HLA binding for cytokine, CTL and ELISPOT assays require positive and negative controls if they are available. For SARS-CoV antigens, the HBcAg-derived H-2b-restricted peptide HBcAg (131-140) AYRPPNAPIL from the spike protein sequence is a suitable negative control.</p>

<p>The activation of transient receptor potential cation channel subfamily V member 1 (TRPV1) is believed to play a role in hyperalgesia, asthma, and hypertension. TRPV1 is important for neuronal pain detection as well as the detection of heat, capsaicin, protons, and the neurotransmitter anandamide.- The scaffold protein AKAP79 targets kinases to phosphorylate TRPV1, however it has been shown that inflammatory intermediates prostaglandin-E2 or bradykinin can activate these kinases creating a route for inflammation to cause hyperalgesia.This product is composed of the TRPV1 interacting residues of AKAP79 reordered into a scrambled sequence and conjugated to the cell penetrating TAT domain at the N-terminus. This product was shown in vivo to have a potent analgesic affect due to interaction with TRPV1 but not affect the pain threshold. This product is a vital tool for research into suitable TRPV1 antagonists.</p>

<p>This peptide 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. Cleavage results in the formation of a thioacyl intermediate between the peptide and SrtA. This intermediate is then resolved by the N-terminus of an (oligo)glycine nucleophile, resulting in the creation of a new peptide bond that links the peptide and its biotin tag to the incoming nucleophile.- This method of protein labelling is known as sortagging.This peptide contains an N-terminal biotin tag for detection and purification.</p>

<p>Calcitonin is a peptide hormone excreted by the thyroid parafollicular cells to regulate calcium and phosphorus levels. Calcitonin acts in opposition to parathyroid hormone (PTH) and vitamin D. Calcitonin functions by inhibiting osteoclast activity in the bones preventing calcium release- there is also inhibition of renal tubular cell reabsorption of calcium and phosphate, so they are excreted preventing a rise in levels.Calcitonin is used for as marker for detection and prognosis of nodular thyroid diseases. Medullary thyroid cancer is one example of the malignant parafollicular cells detectable with the assay, as they present with an increased calcitonin level even at an early stage.Since the discovery of calcitonin over 50 years ago the salmon sourced peptide has been used in numerous treatments including bone metastases, Paget disease, hypercalcaemia, and postmenopausal osteoporosis. The salmon calcitonin has been shown to be equivalent to human form but more active and can be synthetically generated.</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>Histone H3 (1-22) K4Me3 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.Another modification process histones can undergo is biotinylation where the covalent attachment of a biotin molecule is catalysed by the enzyme biotinidase. This cleaves biocytin to generate a biotinyl-thiester intermediate. The biotinyl can then be transferred onto the histone lysine ɛ-amino group which in this case it is covalently attached to Histone 3. Overall the biotinylation sites identified in histone 3 are: K4, K9 and K18. The presence of biotinylated histones have been detected in human cells such as lymphocytes and lymphomas.Lysine 4 of H3 (1-22) has been tri-methylated.</p>

<p>Pro-opiomelanocortin (POMC)-derived peptides act on neurons expressing the Melanocortin 4 receptor (MC4R) to reduce body weight. Setmelanotide is a highly potent MC4R agonist that leads to weight loss in diet-induced obese animals and obese individuals with complete POMC deficiency.The endogenous ligand alpha-melanocyte-stimulating hormone (alpha-MSH) for MC4R has been shown to have a much lower affinity than Setmelanotide, explaining some of the drug's potency. Administration of Setmelanotide to wildtype mice resulted in significant weight loss while  MC4R knockout mice fail to respond. Setmelanotide is in numerous clinical trials and shows promising results. Patients with POMC defects upstream of MC4R show more significant responses to treatment than those with MC4R deficiency or obese controls.</p>

<p>Histone deacetylases (HDACs) are a family of enzymes which are highly evolutionary conserved across all eukaryotes. HDACs modify histones by removing acetyl groups from the tail regions. Histone deacetylation is generally associated with reduced gene expression due to a more compact chromatin state less accessibility for transcription factors (TFs). HDACs are essential for many physiological processes including development and cellular homeostasis. They also play an important role in disease states, including neurodegenerative disorders, genetic diseases and cancers.This peptide is the fluorogenic substrate for assaying histone deacetylase (HDAC) activity in a two-step enzymatic reaction. The assay consists of the initial lysine deacetylation by HDAC followed by the release of the fluorescent group by trypsin. Fluorescence can be detected upon fluorophore release.</p>

<p>Peptide derived from the Gastric inhibitory polypeptide (GIP), 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>Trans-activator of transcription protein (Tat) (47-57) is a cell penetrating cationic peptide derived from the N-terminus of the Tat protein from the human immunodeficiency virus (HIV). Chimerin 1, (CHN1) is a GTPase activating protein specific for RAC GTP-binding proteins, expressed primarily in the brain. CHN1 is involved in signal transduction and is a direct effector of proteins involved in axon guidance. CHN1 is transferred to the plasma membrane and negatively regulates Rho-family small GTPases RAC1 and CDC42, to cause morphological changes to axons by pruning the ends of axon dendrites. As a cell penetrating peptide (CPP) TAT aids in the cellular uptake of molecules. TAT (47-57) can be used to deliver proteins, fluorophores, chelators and DNA to target cells.</p>

<p>An inhibitor of E2F1 and 3a transcription, with a D substituted arginine which confers resistance to proteolysis after pre-incubation in serum. Cytotoxic to several malignant cell lines and human prostate and small cell lung cancer xenografts.</p>

<p>Alpha-Casozepine (alpha-CZP) is a tryptic hydrolysate of bovine milk alphas1-casein. The presence of bile salts facilitates alpha-CZP absorption through a Caco2 monolayer. alpha-CZP shows similarities to benzodiazepines with its anxiolytic-like activity but lack the common side effects of habituation or sedation. alpha-CZP binds to the GABAA receptor at the benzodiazepine site.  alpha-CZP binds with a significantly lower affinity than benzodiazepines.Intraperitoneal administration of Alpha-Casozepine (alpha-CZP) to rodents results in anticonvulsant and sleep-protecting effects. Human administration reduces physiological stress symptoms in stressed and control patients. alpha-CZP modulated neuronal activity in brain regions linked to anxiety regulation in mice.</p>

<p>GRGD-acid is a cell adhesive peptide containing the RGD motif. This enables it the ability to increase cell adhesion and rates of cell growth, differentiation and proliferation.When immobilised onto a Poly(etheretherketone) (PEEK) surface it has been shown to increase cell adhesion and proliferation in MC3T3-E1 cells. GRGD could therefore be used in dental implants.This peptide contains a C-terminal Alexa Fluor 647 florescent dye. A cysteine residue has been added to the C-terminus for conjugation of the dye via the cysteine thiol moiety. AF647 is a bright, far-red-fluorescent dye with excitation between 594 nm and 633 nm, and is pH-insensitive over a wide molar range.</p>

<p>Dipeptide consisting of one glycine and one serine residue with diverse uses. Primary metabolite and bronsted base, forms a complex with Cu(II) acting as a tridentate ligand.Primary metabolites are metabolically or physiologically essential and are directly involved in an organism's development, growth, or reproduction.</p>

<p>Fluorogenic substrate peptide to assay the caspase-like peptidic activity of the 20S proteasome. In its intact state this peptide is non-fluorescent, however when the Rhodamine fluorophore is released upon hydrolysation, fluorescence can be detected. This peptide is therefore a useful tool for analysing enzyme activity.The presence of the D-proline residue on the C terminal of the rhodamine molecule ensures one directional rhodamine cleavage which simplifies fluorescence studies. Rhodamine 110 is a laser grade fluorescent dye with excitation maxima at 496 nm and emission maxima at 522 nm.</p>

<p>The CMX-8933 peptide is a fragment of the goldfish brain neurotrophic factor ependymin which can increases the enzymatic activity of c-Jun N-terminal kinase (JNK), increase the phosphorylation of JNK and c-Jun proteins, and increase cellular levels of c-Jun and c-Fos mRNAs.</p>

<p>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 rise of antibiotic resistance has led to the search for new drug alternatives. Antimicrobial peptides (AMPs) have been identified as a lucrative area for molecule design. The polar fish Pleuronectes americanus expresses polyalanine peptide (pALA) which has been shown to be an AMP against biofilms, and gram-negative bacteria, while not being toxic to mammalian cells. pALA forms an alpha helical conformation that is effective at permeabilising the gram-negative bacteria membrane inducing fatal cell leakage. pALA provides a suitable model for molecule design to hopefully provide new drugs as we enter the post-antibiotic era.</p>

<p>The GHK tripeptide has many attributes which can positively impact human health. GHK can improve tissue repair, exhibit anti-cancer and anti-inflammatory properties, suppress age related molecules and restore chronic obstructive pulmonary disease fibroblasts.The GHK tripeptide is found in the human plasma and binds copper. It exerts its effects through its ability to up regulate and downregulate 4,000 human genes. Due to its ability to protect and regenerate aspects of human health, GHK-Cu can be used in products for skin and hair.Specifically during skin regeneration GHK-Cu can promote the synthesis of collagen and glycosa-minoglycans, increase the rate of wound healing and the formation of blood vessels.A palmitoyl group is present on the N-terminus.</p>

<p>BNP-32, porcine is an N-terminal six amino acid extended form of BNP and henceforth is designated BNP-32. BNP and BNP-32 are found to be the major forms of BNP family in porcine brain.BNP-32 is a cardiac neurohormone and is secreted from the myoendocrine cells of the ventricles of the heart in response to volume expansion and pressure overload it has natriuretic, vasodilatory and cardiovascular homeostatic effects and suppresses the renin-angiotensin-aldosterone system.</p>