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

The present study using immunologic methodology confirms previous observations from this laboratory of an absence of a protease component with arginine esterase activity in plasma of patients with cystic fibrosis. In this study, the pooled plasma from control individuals was activated and partially purified after adsorption on columns of soybean trypsin inhibitor conjugated to Sepharose 4B followed by elution with benzamidine. The fraction was further purified by isoelectrofocusing on polyacrylamide gels. Proteins around the pI range of 5.5 were eluted and utilized to prepare an antiserum. Immunoelectrophoresis of activated plasma samples from control subjects and patients with cystic fibrosis was performed utilizing the antiserum. In controls, four precipitin arcs with residual esterase activity were observed, whereas only three were seen in plasma from patients with cystic fibrosis. Double gel diffusion experiments using specific antisera ruled out the presence of trypsin, chymotrypsin, plasminogen, prothrombin, C1 esterase, alpha one-trypsin inhibitor, and inter-alpha-trypsin inhibitor in the concentrated benzamidine eluate. The antisera to alpha two-macroglobulin gave an immunoprecipitate which was readily stained for proteolytic activity. On immunoelectrophoresis, the alpha two-macroglobulin precipitin band corresponded to the band absent in plasma of patients with cystic fibrosis. In contrast, the alpha two-macroglobulin levels were similar in plasma of control subjects and patients with cystic fibrosis. Using the antiserum to the protein fractith proteolytic activity could be demonstrated in control plasma. One specific enzyme-active "rocket" was absent in plasma of patients with cystic fibrosis. In a double blind study of 15 control samples and 15 samples from patients with cystic fibrosis, a specific "rocket" was shown to be present in 13 control samples and absent in 14 cystic fibrosis samples. alpha two-Macroglobulin was determined by both an immunologic procedure and by its trypsin binding (trypsin protein esterase concentration). The ratio of the immunologic assay to the biologic activity assay was 90 for the normal plasma samples and only 65 for cystic fibrosis samples.
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PMID:Absence of an alpha two-macroglobulin-protease complex in cystic fibrosis. 6 Jul 35

The formation of EAC 4b2a is a two step reaction: first, the temperature- and time-independent binding of C2 to EAC4b2a resulting in EAC4b2 , secondly, the enzymatically triggered conversion of EAC4b2 to EAC4b2a . In the classical cascade of complement activation, the generation of C3 convertase activity is triggered by the C1 esterase, C1-s, which is part of C-1. Evidence is presented that the enzymes trypsin, chymotrypsin, plasmin, and pronase are also able to activate EAC4b2 to EAC4b2a . Kinetic studies showed that the formation of C3 convertase by these enzymes was dependent on concentration, temperature, and time. The optimal conditions were found as follows: trypsin, 2 micrograms/ml (final conc.) for 8 min at 23 degrees C; chymotrypsin 165 micrograms/ml for 18 min at 23 degrees C; plasmin 0.8 units/ml for 15 min at 23 degrees C; pronase 1.25 microgram/ml for 15 min at 23 degrees C. Even under optimal (tmax) conditions the number of generated EAC4b2a differed from enzyme to enzyme: trypsin (= 100%), pronase (58.3%), chymotrypsin (47.9%), and plasmin (12.9%). The enzymes were also able to generate C3 convertase activity from C2 which was adsorbed to EAC1i4b , a C1 inactivator treated and therefore hemolytically inactive intermediate ( EAC1i4b2 ). These findings underline the biological importance of C1 esterase replacing enzymes.
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PMID:Generation of the classical pathway C3 convertase (EAC4b2a) by proteolytic enzymes. 637 57