Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.1 (chymotrypsin)
 10,938 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serine proteinases have the potential to influence the degradation of connective tissue in chronic periodontitis, which may progress episodically at individual tooth sites. Elastase-, chymotrypsin- and tryptase-like proteinase activity in homogenized gingival tissue were measured using, respectively, the selective peptide substrates MeOSuc-Ala-Ala-Pro-Val-AFC. MeOSuc-Phe-Pro-Phe-AFC and Z-Ala-Arg-Arg-AFC. Each tooth site was assayed separately and divided, where appropriate, into gingival tissue and granulomata. Elastase-like activity was detected in only about half of the sites and with large variations. Chymotrypsin-like activity decreased with increasing pocket depth, clinical attachment level, gingival index and gingival bleeding index. Tryptase-like activity did not vary consistently with clinical measures. Chymotrypsin- and tryptase-like proteinase activity were much higher in gingival tissue than in granulomata. These effects are best explained by the likely influence (or lack of influence) of the endogenous serum and tissue inhibitors of serine proteinases, the different cellular origins of the enzymes, and their relative affinities for their substrates.
 ...
PMID:A biochemical study of serine proteinase activities at local gingival tissue sites in human chronic periodontitis. 220 77

The purpose of these studies was to identify some of the extracellular proteolytic enzymes associated with the development and healing of acute inflammatory lesions. Lesions were produced in the skin of rabbits by the topical application of the military vesicant, sulfur mustard (SM). Full-thickness, 1-cm2 central biopsies of the lesions were organ-cultured for one to three days, and the culture fluids were assayed for proteases with a variety of substrates. When compared to culture fluids from normal skin, the culture fluids from both developing and healing SM lesions had three to six times the levels of proteases hydrolyzing two synthetic peptide substrates: (1) t-butyloxycarbonyl-Leu-Gly-Arg-4-trifluoromethylcoumarin-7-amide(Boc-Leu -Gly- Arg-AFC, herein abbreviated LGA-AFC), and (2) N-benzoyl-phenylalanine-beta-naphthyl ester (BPN). LGA-AFC is a substrate for trypsin, plasmin, plasminogen activator, thrombin, kallikrein, and the C3 and C5 convertases; BPN is a chymotrypsin and cathepsin G substrate. The culture fluids did not consistently hydrolyze four other synthetic peptide substrates or the proteins [14C]-casein and [14C]elastin. In order to determine the likely sources of LGA-AFCase and BPNase activity, we counted the number of granulocytes (PMNs), macrophages (MNs) and activated fibroblasts in histologic sections of developing and healing SM lesions, and we measured the levels of these enzymes in serum, in culture fluids of PMN and MN peritoneal exudate cells, and in culture fluids of two fibroblast cell lines. In SM lesions, serum and fibroblasts seemed to be the major source of LGA-AFCase, and serum alone the major source of BPNase. Tissue PMNs and MNs seemed to be only minor sources. The crusts of healing lesions, which were full of dead PMNs, seemed to be a rich source of both enzymes. In the SM lesion culture fluids, whether LGA-AFC and BPN were hydrolyzed by endopeptidases or only by exopeptidases could be determined by evaluating complex formation with alpha-macroglobulin proteinase inhibitors (alpha M). Endopeptidases, but not exopeptidases, are entrapped and inhibited by alpha M, because an internal peptide band in alpha M must first be hydrolyzed before molecular rearrangement (required for proteinase inhibition) occurs. The catalytic site of endopeptidases that are entrapped and inhibited by alpha M is known to remain active on (and reachable by) small synthetic peptide substrates such as LGA-AFC and BPN.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Proteases released in organ culture by acute dermal inflammatory lesions produced in vivo in rabbit skin by sulfur mustard: hydrolysis of synthetic peptide substrates for trypsin-like and chymotrypsin-like enzymes. 304 42

A novel serine proteinase, designated as prostasin, has been purified from human seminal fluid to apparent homogeneity by DEAE-Sepharose CL-6B and aprotinin-affinity chromatography. The purified protein migrates as two close bands with an apparent molecular mass of 40 kDa on SDS-polyacrylamide gel electrophoresis under reducing conditions. It can be labeled with [14C]diisopropyl fluorophosphate and has a pI ranging from 4.5 to 4.8. Sequence analysis reveals that the two protein bands have an identical NH2-terminal amino acid sequence which is different from any known protein sequence in the SwissPro or GenBank data base. The NH2-terminal 20-amino acid sequence shares 50-55% identity with human alpha-tryptase, elastase 2A and 2B, chymotrypsin, acrosin, and the catalytic chains of hepsin, plasma kallikrein, and coagulation factor XI. Prostasin has trypsin-like activity with a pH optimum of 9.0, hydrolyzing peptidyl fluorogenic substrates: D-Pro-Phe-Arg-MCA, D-Phe-Phe-Arg-MCA, D-Val-Leu-Arg-MCA, and Z-Gly-Pro-Arg-AFC. It is inhibited by aprotinin, antipain, leupeptin, and benzamidine. The tissue distribution of prostasin was determined by a newly developed radioimmunoassay. Linear displacement curves for immunoreactive prostasin in body fluids and tissues were parallel with the standard curve of purified prostasin, indicating their immunological identity. Immunoreactive prostatin levels were 8.61 +/- 0.42 microgram/ml in the seminal fluid and 0.201 +/- 0.029 microgram/ml in urine. Prostasin is present at high levels in the prostate gland (143.7 +/- 15.9 ng/mg protein), moderate levels (2-6 ng/mg protein) in colon, lung, kidney, pancreas, salivary gland, liver, and bronchi, but it is not detected in the brain, muscle, testis, ventricle, atrium, and aorta. Immunohistochemical localization reveals that prostasin is present in epithelial cells and ducts of the prostate gland. These studies indicate that prostasin purified from seminal fluid is a novel serine proteinase and originates from the prostate gland.
 ...
PMID:Prostasin is a novel human serine proteinase from seminal fluid. Purification, tissue distribution, and localization in prostate gland. 803 38