Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two alkaline proteases, one splitting preferentially the substrates of chymotrypsin (ATEE) and the other one those of trypsin (BAEE), were separated and partially purified by chromatographic means from human skin extract made in a buffer containing 1.07 mol/1 KC1. The proteins soluble in dilute buffer were removed by a prior extraction. The enzymes could be separated effectively only in the presence of KC1 at a high conc-ntration since large molecular size aggregates or polymers were formed in solutions of low ionic strength. In the presence of 2 mol/1 KC1 the molecular size of the BAEE-hydrolysing enzyme was 120000 and that of the ATEE-hydrolysing enzyme 30000. The ATEE-hydrolysing enzyme was purified by Sephadex G-100 gel filtration and DEAE-cellulose chromatography about 250 fold. It also hydrolysed esters of tryptophane and phenylalanine as well as casein with optimum pH 7.8--8.2. The enzyme was inhibited effectively by LBTI, SBTI and partially by trasylol, TPCK and TLCK, but not by E-600 and SH-modifers. The hydrolysis of ATEE was doubled in the presence of 1 mol/lKCl, NaCl, KBr or NaBr but that of casein was inhibited to some extent. Human serum and alpha-1-antitrypsin inhibited this enzyme but not C1-inactivator. alpha-2-Macroglobulin did not protect if from inhibition by SBTI. The BAEE-hydrolysing enzyme was purified by Sephadex G-100 gel filtration and hydroxylapatite chromatography about 30 fold. It also split other esters of substituted basic amino acids as well as BAPA and histone proteins with optimum pH 7.5--8.2. It was inhibited by Trasylol and TLCK, but not by LBTI, SBTI, OMTI, TPCK, E-600, SH-modifiers, human serum, C1-inactivator or alpha-1-antitrypsin. Neither of these enzymes is exactly similar to any one of the enzymes so far separated from human tissues or fluids.
...
PMID:Human skin proteases: separation and characterization of two alkaline proteases, one splitting trypsin and the other chymotrypsin substrates. 120 Jul 4

The time-courses of proteolytic activities in pancreatic tissue and the contents of the small intestine (the intestinal contents) were determined in rats maintained on a diet containing 30% of various proteins after a switchover from a diet containing 12% casein. 1. The proteolytic activity of the pancreatic tissue quickly responded to change of dietary proteins--within 1 to 6 days--with respect to organ weight, nitrogen content and proteolytic activity, in rats receiving diets containing 30% casein, ovalbumin, lactalbumin, gluten, gelatin or zein. 2. However, the proteolytic activity in the intestinal contents did not necessarily coincide with the pancreatic digestive function; an approximately threefold increase of enzyme activity was demonstrated on the fifth day of feeding in rats receiving gluten. 3. The proteolytic activity in the intestinal contents returned to the initial level on the eighth day in the gluten-fed rats, but those rats maintained on a lysine-supplemented gluten diet exhibited no such elevation of proteolytic activity. 4. No significant difference in pancreatic composition was shown up to the eighth day between the group receiving gluten alone in diet and that receiving the same diet but supplemented with lysine, under the condition of equally restricted food intake. Intestinal trypsin and chymotrypsin levels, however, were higher in the gluten-fed rats, suggesting that the depressed rate of enzyme inactivation in the small intestine might be the principal cause of the finding described under (2) above.
...
PMID:Effect of dietary protein on proteolytic activities in the pancreatic tissue and contents of the small intestine in rats. 121 81

Two bitter peptides, H-Phe-Tyr-Pro-Glu-Leu-Phe-OH (I) and H-Val-Glu-Val-Phe-Ala-Pro-Pro-Phe-OH (II) were isolated from casein, hydrolyzed by alpha-chymotrypsin. The hexapeptide is cleaved by thermolysine between Glu and Leu. The two fragments are bitter too. A bitter dodecapeptide (III) was obtained 20 min hydrolysis of casein with trypsin. On account of amino acid composition and N-terminus peptide III is probably identical with a peptide from a 12 hrs hydrolyzate, described in 1970 by Matoba. The peptides I and III have equal taste tresholds in the range of 0.08-0.10 muM/ml.
...
PMID:[Bitter peptides of casein isolated by hydrolysis with alpha-chymotrypsin and trypsin (author's transl)]. 122 11

Some N,N'-bis(3-substituted benzylideneaminopropyl) piperazines were synthesized and characterized by their sharp melting points and elemental analyses. These substituted piperazines possessed anti-inflammatory activity, and the protection afforded by these compounds against carrageenan-induced edema ranged from 23 to 67%. The antiproteolytic activity of these piperazines was reflected by their ability to inhibit in vitro hydrolysis of bovine serum albumin and casein by trypsin. The inhibition of trypsin-induced hydrolysis was concentration dependent and competitive in nature.
...
PMID:Synthesis of N,N'-bis(3-substituted benzylideneaminopropyl)-piperazines and their anti-inflammatory, antiproteolytic, and anticonvulsant properties. 126 90

The effect of sodium sulphite, cysteine, glutathione, mercaptoethanol and dithioerythritol (0.1-10 mmol l-1) on the activity of proteases of Microsporum gypseum was studied using azocasein, cross-linked bovine serum albumin and keratin as substrates. With the substrate without disulphide bonds (casein) no stimulation was found, and reducing agents inhibited proteolysis in most cases. With the remaining two substrates, all substances enhanced the activity of proteases probably through the cleavage of the substrate disulphide bonds. Sulphite was more effective than the four used thiols and enhanced the activity against serum albumin up to 3.2 times and against keratin up to 2.9 times. Using sulphitolysed sheep wool, keratinolytic activity increased after sulphitolysis of more than 20% of disulphide bonds. With the fully sulphitolysed wool the activity increased 43 times. The obtained results support the author's hypothesis on keratin degradation by sulphite excretion prior to attack by fungal proteases. Stimulation of proteolysis and keratinolysis by cleavage of disulphide bonds is not specific for dermatophytic proteases because trypsin and pronase behaved similarly in the experiments.
...
PMID:Effect of reducing agents on proteolytic and keratinolytic activity of enzymes of Microsporum gypseum. 128 10

A proteolytic enzyme from L. muta stenophrys was isolated by gel filtration on Bio Gel P-100 followed by FPLC on MONO S column. The enzyme exhibited proteolytic activity toward casein, hemoglobin and fibrinogen with a pH optimum around 10. The activity was inhibited by EDTA while trypsin inhibitors were not inhibitory. It is a glycoprotein, Mr 14 kDa with a high content of Asp, Glu, and Leu residues and a low content of Cys and Trp. The protease is devoid of myotoxic, hemorrhagic, esterolytic and amidolytic activities. It lyses the alfa and beta chains of human fibrinogen and releases kinin from L.M.W. kininogen. No release of histamine was observed upon incubation with mast cells.
...
PMID:Characterization of a proteolytic enzyme from Lachesis muta venom (Serpentes: Viperidae). 130 16

An inhibitory protein for the 20S proteasome (also known as macropain, the multicatalytic proteinase complex and 20S proteinase) has been purified from bovine red blood cells. The inhibitor has an apparent molecular weight of 31,000 on SDS-PAGE and appears to form multimers under nondenaturing conditions. This protein inhibited all three of the putatively distinct catalytic activities of proteasome A (the active form of the proteinase) characterized by the hydrolysis of synthetic peptides such as Z-VLR-MNA, Z-GGL-AMC or Suc-LLVY-AMC and Z-LLE-beta NA. The inhibitor also prevented the hydrolysis of large protein substrates such as casein, lysozyme and bovine serum albumin. Proteasome L (the latent form of the proteinase) does not degrade these large protein substrates, but does hydrolyze the three synthetic peptides at rates similar to those by proteasome A. The inhibitor inhibited only two of these peptidase activities of proteasome L (hydrolysis of Z-GGL-AMC and of Z-LLE-beta NA or Suc-LLVY-AMC); it had no effect on the hydrolysis of Z-VLR-MNA. The inhibitor was specific for inhibition of the proteasome and had no effect on the activity of any other proteinase tested including trypsin, chymotrypsin, papain, subtilisin and both isoforms of calpain. Kinetic analysis indicates that the inhibitor interacted with the proteasome by a mechanism involving tight-binding. Because the proteasome appears to be a key component of the ATP/ubiquitin-dependent pathway of intracellular protein degradation, the inhibitor may represent an important regulatory protein of this pathway.
...
PMID:Purification and characterization of a protein inhibitor of the 20S proteasome (macropain). 131 59

Protease activity is associated with the coadhesion of Actinomyces viscosus and Porphyromonas gingivalis. To try to distinguish whether the recognition/adhesion or degradative functions of proteases are more crucial for coadhesion, we determined the effect of trypsin and other purchased proteases and proteins on coadhesion when they were incorporated in the coadhesion assay buffer or when A. viscosus cells were pretreated with trypsin. Coadhesion was measured by the decrease in turbidity caused by the absorption of A. viscosus cells from aqueous suspension by P. gingivalis-coated hexadecane droplets. Pretreatment of A. viscosus with trypsin had no obvious effect on the kinetics of coadhesion. Likewise, trypsinization of A. viscosus failed to aid or enhance coaggregation by chemically induced, trypsin activity-deficient mutants of B. gingivalis. In contrast, incorporating trypsin in the buffer during the coadhesion assay yielded a concentration-dependent inhibition of coadhesion greater than the inhibition found with the same concentration of other proteases. Coadhesion was also impaired to a greater extent by similar wt/vol concentrations of nonproteolytic proteins (bovine serum albumin (BSA), defatted BSA, gelatin, and casein), by antisera against whole P. gingivalis cells and fimbriae, by preimmune serum, and by the amino acid arginine but not lysine. These findings suggest that the role of proteases in coadhesion is not solely to enzymatically "prime" A. viscosus for more avid coadhesion and that their role as potential protein or peptide seeking adhesins should be considered.
...
PMID:Inhibition of Actinomyces viscosus--Porphyromonas gingivalis coadhesion by trypsin and other proteins. 132 96

We have studied the effect of such milk proteins as caseins, lactalbumin, and lactoglobulin, on proliferation and immunoglobulin production of human-human hybridoma HB4C5 cells. It was found that alpha-, beta-, and kappa-caseins stimulated both proliferation and IgM product ion of human-human hybridoma HB4C5 cells, while the activities of alpha-lactalbumin and beta-lactoglobulin were negligible. To localize the active sites of these caseins, effect of protease treatments on the activities were examined. When caseins were digested with trypsin, casein digests stimulated proliferation of the hybridoma, but not their IgM production. When kappa-casein was digested with chymosin and fractionated to p-kappa-casein and glycomacropeptide, both fragments stimulated proliferation of the cells, but only p-kappa-casein fragment stimulated IgM production. These results indicate that kappa-casein has at least two proliferation stimulating sites and an IgM production stimulating site in the p-kappa-casein region.
...
PMID:Stimulation of proliferation and immunoglobulin production of human-human hybridoma by various types of caseins and their protease digests. 136 81

The effect of dietary protein on enzyme activity of pancreatic juice was studied in ten growing, castrated, Large White male pigs. Animals, fitted with permanent cannulas in the pancreatic duct and in the duodenum, were divided into two groups receiving either casein or rapeseed concentrate as a protein source. After a 15 d adaptation period to the experimental diet, the volume of pancreatic secretion was significantly higher, whereas the protein concentration was lower in the casein group compared with the rapeseed group. No statistical difference was observed in the daily protein output between groups. Total secreted activities of carboxypeptidase A (EC 3.4.17.1), and elastase (EC 3.4.21.36) were higher in the casein group during the nocturnal period, whereas total activities of trypsin (EC 3.4.21.4), chymotrypsin (EC 3.4.21.1), carboxypeptidase B (EC 3.4.17.2) and amylase (EC 3.2.1.1) in pancreatic secretions during the post-prandial periods were increased by the ingestion of the rapeseed diet. It is concluded that the pancreatic enzyme secretion is sensitive to the nature of the protein ingested.
...
PMID:Effects of diets containing casein and rapeseed on enzyme secretion from the exocrine pancreas in the pig. 137 39


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---