Peptidi

Auto-inducing peptide (AIP) is a cyclic thiolactone quorum sensing peptide from Staphylococcus aureus which is responsible for activating the agr response. AIP is released from the bacteria and its extracellular concentration is then sensed by a two-component system on the bacterial surface, AgrC and AgrA. AgrC is the membrane histidine kinase receptor and AgrA is a response regulator- upon binding of AIP, AgrC phosphorylates AgrA.AIP accumulates during growth activating an AgrC and AgrA cascade when it reaches a critical signal level. This cascade activates P2 and P3 promoters which autoactivate the agr system and upregulate RNAIII transcription. RNAIII regulates the expression of virulence factors including toxins, super-antigens, and exo-enzymes. Extensive research to identify AIP:AgrC inhibitors aims to find therapeutics against pathogens.AgrD is the precursor peptide of AIP, and AgrB is an integral membrane endopeptidase essential to biosynthesize AIP. This AIP system is conserved among many Gram-positive bacteria. S. aureus strains are categorized into four groups (I-IV) according to their AIP signal and cognate extracellular receptor, AgrC.  AIP-I has the characteristic five-residue thiolactone ring with a short N-terminal extension. AIP-I has been used to generate a biosensor for the detection of S. aureus in nanomolar range for use in hospital settings.

Fmoc-Cys((R)-2,3-di(palmitoyloxy)-propyl)-OH is a versatile building block that is useful for the synthesis of complex compounds. This compound has been shown to be a useful intermediate in the synthesis of pharmaceuticals, organic dyes and research chemicals. Fmoc-Cys((R)-2,3-di(palmitoyloxy)-propyl)-OH is a fine chemical that is used as a reagent in organic synthesis. It has CAS No. 139573-77-6 and can be used as a speciality chemical or reaction component.

The Aβ E22delta mutant (Osaka mutation) is more resistant to degradation by two major Aβ-degrading enzymes, neprilysin and insulin-degrading enzyme.  It also shows unusual aggregation properties with enhanced oligomerization but no fibrilization.

Angiotensin-IV is primarily produced from angiotensin-III by the removal of an arginine residue from the N-terminal by membrane alanyl aminopeptidase N (AP-N). Ang-IV can however also be formed by the action of aminopeptidases on Ang-I directly.Ang-IV has been shown to enhance cognitive functions, although how it does this in still unclear. It has been suggested that Ang-IV is able to inhibit the insulin-regulated aminopeptidase (IRAP) receptor in the brain (originally defined as the AT(4) receptor). IRAP is a single-spanning transmembrane zinc-metallopeptidase that belongs to the M1 family of aminopeptidases and its substrates include vasopressin, somatostatin, and cholecystokinin. The half-life of these compounds are prolonged when IRAP is inhibited by Ang-IV, and this may result in the enhanced cognitive abilities seen with Ang-IV treatment. c-Met, a tyrosine kinase receptor that binds hepatocyte growth factor (HGF) has also been proposed as an Ang IV targets. c-Met is associated with memory and learning consolidation.

[Ala144]-PLP (139-151) is the Ala 144 form of Proteolipid protein (PLP), an epitope of immunodominant encephalitogenic PLP and is involved in promoting encephalomyelitis.

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-nucleophile, resulting in the creation of a new peptide bond that links the peptide and its fluorescent- to the incoming nucleophile.- This method of protein labelling is known as sortagging5-Carboxytetramethylrhodamine (5-TAMRA) is a widely used fluorescent dye which excites at 546 nm and emits at 579 nm

Glucagon-like peptide (GLP)-1 is a gastrointestinal peptide hormone with multiple roles in relation to metabolism. The primary role of GLP-1 is increasing insulin secretion in the presence of high plasma glucose levels, in addition, GLP-1 also suppresses glucagon secretion from the pancreas. GLP-1 slows down gastric emptying and regulates appetite, both valuable in reducing food intake and body weight. These roles of GLP-1 make it a useful target in the management of type 2 diabetes mellitus (T2DM).GLP-1 exerts its effects by binding to and activating the class B G protein-coupled receptor (GPCR): GLP-1 receptor (GLP-1R). Receptor activation in turn activates signalling pathways which culminates in insulin secretion via CAMP and Ca2+ signalling.Recently evidence has increased for GLP-1 playing a cardio-protective role as well as regulating immune responses and even in kidney function. GLP-1 may also exert neuroprotective and neurotropic effects as it can decrease endogenous levels of amyloid-β (Aβ) and prevent Aβ-induced cell death.This peptide contains an N-terminal Biotin tag for simple detection and purification.

PAR2 plays a particular role in protecting the gastric mucosa mediated by capsaicin-sensitive sensory neurons. PAR2 also serves to aid in gut smooth muscle motility- colon inflammation pathway- hyperalgesia and is also anti-inflammatory in other circumstances.Development of selective agonists for PAR2 are crucial for research. (2-Furoyl)-LIGRL-amide is a far more potent agonist than the native PAR2 activating peptide SLIGRL-NH2. In mice, oral administration conferred cytoprotection from gastrointestinal lesions. However, it was inhibited by capsaicin pre-treatment.

Alpha-synuclein (1-13) 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.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.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.The methionine at position 5 is oxidised and the oxidation of methionine is common in neurodegenerative diseases and promotes the accumulation of altered α-synuclein. Furthermore when these methionine residues are oxidised, methionine sulfoxides are produced.

Cell permeable peptide where the amyloid forming sequence is homologous to a nucleating sequence from the human Tau protein (306VQIVYK311). Forms long lived oligomers that are taken up by endocytosis and is cytotoxic in multiple cell lines.- Co-localizes with pathological hyperphosphorylated forms of Tau in vitro.

Acetylated α-synuclein (1-13) 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.

This anti-microbial peptide (AMP) has been shown to cause lysis of several human cancer cell lines. Macropin-2 is most potent against CCRF-CEM T lymphoblastoid (human acute lymphoblastic leukemia) cells. At higher concentrations Macropin-2 also causes lysis of human umbilical vein endothelial cells (HUVEC), rat intestinal epithelial cells (IEC), human cervix carcinoma (HeLa) cells and human colon adenocarcinoma (SW480). Macropin-1 is also available in our catalogue.

Broad-spectrum antibacterial, active against multidrug-resistant Gram-negative bacteria. Acts though permeabilizing the bacterial membrane and also shows anti-inflammatory activity via a TLR4-mediated NF-KB signaling pathway. Significantly improves survival in a mouse sepsis model.

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.

Peptide H-CYPYDVPDYASLRSL-OH is a Research Peptide with significant interest within the field academic and medical research. This peptide is available for purchase at Cymit Quimica in multiple sizes and with a specification of your choice.

Peptide H-GTCACTC-OH is a Research Peptide with significant interest within the field academic and medical research. This peptide is available for purchase at Cymit Quimica in multiple sizes and with a specification of your choice.

Peptide H-LPDPSKPSKRSFIED-OH is a Research Peptide with significant interest within the field academic and medical research. This peptide is available for purchase at Cymit Quimica in multiple sizes and with a specification of your choice.