Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To provide a rational basis for pancreatic enzyme replacement therapy, we evaluated, in six patients with advanced pancreatic insufficiency, the effects of various treatment regimens on fecal fat and nitrogen balance and on duodenal recovery of ingested pancreatic enzymes after a solid test meal. The combination of cimetidine (an H2-receptor antagonist) and pancreatin, each given by mouth, produced significantly higher postprandial duodenal recoveries and concentrations of trypsin and lipase (P less than 0.05). Steatorrhea was reduced in all patients and abolished in four of the six. In the dosages used, neither enteric-coated enzymes nor supplemental neutralizing antacids were more effective than pancreatin alone in decreasing steatorrhea or improving duodenal enzyme delivery. Cimetidine may be a useful adjunct to oral pancreatic extract therapy in some patients with severe pancreatic insufficiency who fail to respond to pancreatic enzyme replacement alone.
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PMID:Comparative effects of antacids, cimetidine and enteric coating on the therapeutic response to oral enzymes in severe pancreatic insufficiency. 2 May 72

For comparative studies on the esterase activities of thrombin and trypsin N(alpha)-arylsulfonyl-L-arginine methyl esters were synthetised containing in aromatic ring substituents of different polar nature, size and hydrophobicity. The kinetics of their hydrolysis by thrombin and trypsin were measured. Values of Km and kcat in steady-state conditions were determined. It was shown, that thrombin-catalysed hydrolysis was more sensitive than that of trypsin to the nature of substituents of arylsulfonyl group and determined by their polar and steric effects. A line correlation between specificity constants (kcat/Km) and sigma and Es of substituents were demonstrated. The difference in reactivity of compounds under investigation is suggested to depend on alterations of stability of hydrogen bond between arylsulfonylamide nitrogen atom of substrate and the active center of the enzyme due to changes in the acidity of the arylsulfonylamide group affected by substituent of the benzene ring.
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PMID:[Dependence of thrombin- and trypsin-catalyzed hydrolysis of N-alpha-arylsulfonyl-L-arginine methyl esters on the structure of acylamide part of substrates]. 2 Sep 97

Reversible unfolding of bovine chymotrypsinogen A in 2H2O either by heating at low pH or by exposure to 6 M guanidinium chloride results in the exchange of virtually all the nitrogen-bound hydrogens that give rise to low-field 1H NMR peaks, without significant exchange of the histidyl ring Cepsilon1 hydrogens. These preexchange procedures have enabled the resolution of two peaks, using 250-MHz correlation 1H NMR spectroscopy, that are attributed to the two histidyl residues of chymotrypsinogen A. Assignments of the Cepsilon1 hydrogen peaks to histidine-40 and -57 were based on comparison of the NMR titration curves of the native zymogen with those of the diisopropylphosphoryl derivative. Two histidyl Cepsilon1 H peaks were also resolved with solutions of preexchanged chymotrypsin Aalpha. The histidyl peaks of chymotrypsin Aalpha were assigned by comparison of NMR titration curves of the free enzyme with those of its complex with bovine pancreatic trypsin inhibitor (Kunitz). The NMR titration curves of histidine-57 in the zymogen and enzyme and histidine-40 in the zymogen exhibit two inflections; the additional inflections were assigned to interactions with neighboring carboxyl groups: aspartate-102 in the case of histidine-57 and aspartate-194 in the case of histidine-40 of the zymogen. In bovine chymotrypsinogen A in 2H2O at 31 degrees C, histidine-57 has a pK' of 7.3 and aspartate-102 a pK' of 1.4, and the histidine-40-aspartate-194 system exhibits inflections at pH 4.6 and 2.3. In bovine chymotrypsin Aalpha under the same conditions, the histidine-57-aspartate-102 system has pK' values of 6.1 and 2.8, and histidine-40 has a pK' of 7.2. The results suggest that the pK' of histidine-57 is higher than the pK' of aspartate-102 in both zymogen and enzyme. A significant difference exists in the structure and properties of the catalytic center between the zymogen and activated enzyme. In addition to the difference in pK' values, the chemical shift of histidine-57, which is highly abnormal in the zymogen (deshielded by 0.6 ppm), becomes normalized upon activation. These changes may explain part of the increase in the catalytic activity upon activation. The 1H NMR chemical shift of the Cepsilon1 H of histidine-57 in the chymotrypsin Aalpha-pancreatic trypsin inhibitor (Kunitz) complex is constant between pH 3 and 9 at a value similar to that of histidine-57 in the porcine trypsin-pancreatic trypsin inhibitor complex [Markley, J.L., and Porubcan, M. A. (1976), J. Mol. Biol. 102, 487--509], suggesting that the mechanisms of interaction are similar in the two complexes.
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PMID:Zymogen activation in serine proteinases. Proton magnetic resonance pH titration studies of the two histidines of bovine chymotrypsinogen A and chymotrypsin Aalpha. 3 98

T cell blasts activated in the mixed lymphocyte reaction (MLR) carry on their surface stimulator alloantigens which can be removed by treatment of the blasts with trypsin. After overnight incubation in trypsin-free medium, the treated cells exhibit specific alloantigen binding ability: they bind much more effectively cellular material, either obtained from the corresponding MLR supernatant or released by nitrogen cavitation from fresh cells from the stimulating strain, than that from an unrelated H-2 different strain. Trypsin-treated cells which have been incubated in the presence of low concentrations of puromycin are unable to bind stimulator cell fragments.
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PMID:Antigen recognition by T cells activated in the mixed lymphocyte reaction: specific binding of allogeneic cell material after removal of surface-bound antigen by trypsin. 6 88

Fc5mu fragments were purified from a trypsin digest of native IgM by gel filtration and isoelectric focusing. Polyacrylamide gel electrophoresis of Fc5mu fragments in sodium dodecyl sulphate disclosed a major and a minor band with molecules of 320,000 and 285,000 daltons, respectively. The mu chain fragments showed a molecular weight of 34,500. After reduction of the Fc5mu fragments to free mu chain fragments and J chain removal of the reducing agent by dialysis for 24 h under nitrogen in the presence of Zn ions gave non-covalently linked Fc5mu fragments. This shows that the non-covalent interactions operating between the mu chains of non-covalently linked native IgM are present in the C-terminal part of the mu chains. Additional dialysis in the presence of Zn and Cu ions resulted in the formation of covalently linked Fc5mu fragments.
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PMID:Studies on IgM polymerization: reassociation to non-covalently and covalently linked Fc5mu fragments. 9 32

Metabolic alterations in immature rabbit joint tissue were examined following in vitro and in vivo exposure to the alkylating agents Thiotepa and nitrogen mustard. Brief exposure in vitro to either agent resulted in marked suppression of incorporation of radiolabeled precursors of protein, RNA, and glycosaminoglycan synthesis in articular cartilage, which was partially reversible after Thiotepa exposure. In vivo, nitrogen mustard has little effect on synovium and transient inhibitory effects on cartilage vital processes, whereas Thiotepa caused a prolonged inhibition of synovial metabolism with little effect on cartilage. Autoradiographic localization of labeled agents indicated that synovial tissue and cartilage were readily penetrated by nitrogen mustard, but only a few synovial lining cells and superficial chondrocytes were labeled with 35S-Thiotepa. Furthermore, trypsin significantly reduced labeling of cartilage with 14C-nitrogen mustard. These data suggest that alkylating agents differentially affect metabolic processes in joint tissues in vivo and that with Thiotepa, this interference occurs primarily in the synovium. The degree of interference is apparently dependent upon the time of exposure to the agents and the relative DNA-RNA synthetic activity of the joint tissue.
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PMID:Acute metabolic effects of nitrogen mustard and thiotepa on rabbit articular cartilage and synovium. 11 Mar 38

The effect of Bunium Persicum oil on the indices of lipid-lipoid and protein-nitrogen metabolism and of the enzymes (histidase, arginase, transamidinase, trypsin and trypsin inhibitor) reflecting the function of the liver and pancreas was studied in experiments on white rats. There was an improvement of the indices of protein nitrogen metabolism in administration of the oil alone and combined with ethanol and CCl4. At the same time the content of total lipids and cholesterol in the blood serum and in the liver increased. The activity of the enzymes of the blood serum, liver homogenates and the pancreas reflected organ specificity and changed simultaneously with alterations in the general trend of the metabolism.
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PMID:[Experimental study of the action of Bunium persicum oil on the functional state of the liver and pancreas]. 15 84

The effect of gamma irradiation (60Co) of different varieties and breeding lines of dry field beans (Phaseolus vulgaris) on chick growth was determined using a chick growth assay in which the diet contained approximately 50% beans. Total protein (N X 6.25) in beans was not changed appreciably by irradiation (21 Mrad) but protein solubility in water was decreased. Irradiation increased in vitro enzymatic digestibility of bean protein by pepsin and by a mixture of trypsin, chymotrypsin and peptidase. In the bioassay the diet was formulated to derive half of the total protein (22.6%) from beans. Autoclaved Pinto and Pink beans gave significantly better growth than Red Mexican and White Pea beans. The differences between Red Mexican and White Pea beans were not significant except for Red Mexican breeding line number RS-59. The nutritional value of all varieties of beans, based on chick growth, was significantly improved by gamma irradiation. The irradiation treatment of beans tended to increase nitrogen retention by chicks and decrease uric acid nitrogen excretion in relation to nitrogen intake.
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PMID:Effect of gamma irradiation on nutritional value of dry field beans (Phaseolus vulgaris) for chicks. 44 72

Embryonic and early postembryonic development of the carp is associated with an increase in the content of soluble proteins and nitrogen of non-protein nitrogenous components. Simultaneously, the activity of trypsin-like and chemotrypsin-like peptide hydrolases increases together with the increase in the degree of proteolysis. These data suggest that the development of carp embryos and early larva is accompanied by intensification of two opposite processes--synthesis and catabolism of proteins. The observed changes are more evident in early postembryonic period as compared with the early stages of embryogenesis.
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PMID:[Proteinase activity in the early developmental stages of the carp, Cyprinus carpio]. 56 88

Pancreatitis was induced in 11 miniature pigs by infusing a bile salt-trypsin solution into the pancreatic duct. Seven animals served as sham-operated controls. Serum ionized calcium, total calcium, albumin, total protein, inorganic phosphorus, urea nitrogen, magnesium, insulin, glucagon, and hematocrit were determined every six to 12 h over a period of one week in both test and control animals. We observed significant decreases in ionized and total calcium, modest decreases in albumin, and significant increases in the inorganic phosphorus, urea nitrogen, and hematocrit in the pancreatitic pigs. The latter two findings were consistent with early acute hypovolemia. Glucagon and insulin appeared to play no role in the hypocalcemia. Glucagon concentrations increased to the same degree in both test and control animals, probably as a result of the stress of being handled and operated on. The highest concentrations of inorganic phosphorus and the lowest concentrations of both ionized and total calcium were seen 18 h after the induction of pancreatitis in the test animals. These findings suggest that parathyrin (parathormone) was not being secreted in adequate amounts, or that the target organs were unresponsive to parathyrin.
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PMID:Biochemical changes in a porcine model of acute pancreatitis. 65 76


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