chymotrypsin c

Chymotrypsin C (abbreviated for CTRC), also known as caldecrin or elastase4, is a digestive enzyme of the peptidase S1 family. This enzyme is synthesized as an inactivate chymotrypsinogen. On cleavage by trypsin into two parts that activate each other by removing two small peptides in a trans-proteolysis, chymotrypsin C produced. N-linked glycosylation of human CTRC is required for efficient folding and secretion, however, the N-linked glycan is unimportant for enzyme activity or inhibitor binding. It has been proposed that CTRC is a key regulator of digestive zymogen activation and a physiological co-activator of digestive carboxypeptidases proCPA1 and proCPA2. Mutations that abolish activity or secretion of CTRC increase the risk for chronic pancreatitis. It's speculated that CTRC might regulate pancreatic cancer cell migration in relation to cytokeratin 18 expression. The pancreatic cancer cell migration ability was downregulated in pancreatic cancer Aspc-1 cells that overexpressed CTRC, whereas the cell migration ability was upregulated in Aspc-1 cells in which CTRC was suppressed.

Binds to and inhibits kallikreins. Inhibits trypsin but not chymotrypsin or elastase. Serpin A3K Protein, Rat, Recombinant (His & Myc) is expressed in E. coli expression system with N-10xHis and C-Myc tag. The predicted molecular weight is 52.0 kDa and the accession number is P05545.

As protease inhibitors, serpins have an array of functions including regulating blood clotting, the complement pathway, extracellular matrix remodeling, and cell motility. Serpin G1 is a serine protease inhibitor protein. It is the largest member among the serpin class of proteins. Remarkably, Serpin G1 has a 2-domain structure, unlike most family members. The C-terminal serpin domain is similar to other serpins, and this part of Serpin G1 provides the inhibitory activity. The N-terminal domain is not essential for Serpin G1 to inhibit proteinases and has no similarity to other proteins. The main function of Serpin G1 is the inhibition of the complement system to prevent spontaneous activation. Serpin G1 is an acute phase protein and circulates in blood at levels of around 0.25g/L, whose levels rise 2-fold during inflammation. Although named after its complement inhibitory activity, Serpin G1 also inhibits proteinases of the fibrinolytic, clotting, and kinin pathways. Most notably, Serpin G1 play a potentially crucial role in regulating important physiological pathways including complement activation, blood coagulation, fibrinolysis and the generation of kinins. It is also the most important physiological inhibitor of fXIIa, chymotrypsin and plasma kallikrein.

Chymotrypsinogen B (CTRB1) is a 263 amino acid protein with signal peptide (1-18) and Chymotrypsinogen B (19-263). Chymotrypsinogen B have three chains:Chymotrypsin B chain A(19-31), Chymotrypsin B chain B(34-164), Chymotrypsin B chain C (167-263). Chymotrypsinogen B is a Serine Protease Hydrolase secrets into gastrointestinal tract as the inactive precursor Chymotrypsinogen.

This enzyme, isolated from small intestine, specifically inactivates the apo forms of a certain group of intracellular pyridoxal phosphate-requiring enzymes. It has chymotrypsin-like specificity towards small substrates. Mcpt2 Protein, Rat, Recombinant (His & Myc) is expressed in E. coli expression system with N-6xHis and C-Myc tag. The predicted molecular weight is 30.5 kDa and the accession number is P00770.

Mast Cell Protease 1 (MMCP-1), also known as MCP-1, MCPT-1 and β-chymase, is a member of the Chymase family of chymotrypsin-like serine proteases. MCPT-1 is a 26 kDa β-chymase that is a component of mast cell granules. It is a 226 amino acid (aa) protein that has a conserved pattern of six cysteines and one potential glycosylation site. The granule-derived mouse mast cell proteases-1 and -2 (mMCP-1 and -2) colocalize in similar quantities in mucosal mast cells but micrograms of mMCP-1 compared with nanograms of mMCP-2 are detected in peripheral blood during intestinal nematode infection. mMCP-1 isolated from serum is complexed with serpins and both the accumulation and the longevity of mMCP-1 in the blood is due to complex formation, protecting it from a pathway that rapidly clears mMCP-2, which is unable to form complexes with serpins. The mucosal mast cell (MMC) granule-specific beta-chymase, mouse mast cell protease-1 (mMCP-1), is released systemically into the bloodstream early in nematode infection before parasite-specific IgE responses develop and TGF-beta1 induces the constitutive release of mMCP-1 by homologs of MMC in vitro. Expression of mMCP-1 is largely restricted to intraepithelial MMC and is thought to play a role in the regulation of epithelial permeability. Its activation is completed by the removal of a two residue N-terminal propeptide by a dipeptidyl peptidase (Cathepsin C). MCPT-1 is upregulated in the intestine in response to nematode infection, or systemic mucosa in response to anaphylaxis. Like human α-chymase, MCPT-1 is capable of the conversion of angiotensin I to angiotensin II, which plays a key role in the regulation of arterial pressure. The intestinal inflammation associated with gastrointestinal helminths is partly mediated by mMCP-1.

SERPINB3, also known as SCCA-1, belongs to the serpin family. Serpins are a group of proteins with similar structures that were first identified as a set of proteins able to inhibit proteases. The acronym serpin was originally coined because many serpins inhibit chymotrypsin-like serine proteases. SERPINB3 is expressed in some hepatocellular carcinoma (at protein level). Its expression is closely related to cellular differentiation in both normal and malignant squamous cells. It seems to also be secreted in plasma by cancerous cells but at a low level. SERPINB3 significantly attenuates apoptosis by contrasting cytochrome c release from the mitochondria and by antichemotactic effect for NK cells. It may act as a protease inhibitor to modulate the host immune response against tumor cells and may be involved in the malignant behavior of squamous cell carcinoma cells.

SERPIN G1 is a member of the serpin family, The C-terminal serpin domain is similar to other serpins, and this part of C1-INH provides the inhibitory activity. SERPIN G1 is involved in the inhibition of the complement system to prevent spontaneous activation. SERPIN G1 may play a potentially crucial role in regulating important physiological pathways including complement activation, blood coagulation, fibrinolysis and the generation of kinins. SERPIN G1 prevents the proteolytic cleavage of later complement components C4 and C2 by C1 and MBL. SERPIN G1 is a very efficient physiological inhibitor of FXIIa, plasma kallikrein and fXIa, and could inhibit chymotrypsin and kallikrein. It forms a proteolytically inactive stoichiometric complex with the C1r or C1s proteases in the C1 complex of classical pathway of complement. Activation of the C1 complex is under control of the C1-inhibitor.