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

Ovarian carcinoma contains an antigen (TA) which is stable at 100 degrees. Rabbit antisera to glycoprotein-rich extracts of tumors detect TA in 70 per cent of ovarian malignancies, in some benign ovarian cysts, certain normal lung preparations, normal cervix, and squamous-cell carcinoma of the cervix. Highest levels may be associated with mucin secretion. No detectible antigen was present in normal ovary, plasma, A, B, and O erythrocytes, leukocytes, placenta, brain, heart, liver, corpus uteri, spleen, skeletal muscle, or kidney. Prolonged digestion of boiled tumor extracts with papain, trypsin, chymotrypsin, on Sephadex G-150 corresponding to a globular protein of 27,000 to 36,000 molecular weight. A beta-globulin mobility is seen in immunoelectrophoresis. It appears that TA differs in tissue specificity and molecular size from other known ovarian cancer associated antigens.
 ...
PMID:A thermostable antigen associated with ovarian cancer. 6 15

Bovine erythrocyte treatment with chymotrypsin, trypsin, pronase, papain, or ficin eliminated or weakened the reactivity of 18 of the 47 blood group factors which were examined. Thirteen of the affected factors were from the B system, and one each was from the C, FV, L, M, and R'S' systems. Variation attributable to pheno-group (allele) or genotype influences was observed in the effects upon six of the factors. Ficin-treated V/V, but not F/V or F/F, cells were rapidly lysed by normal rabbit serum (complement control). Absorptions with pronase-treated V positive cells indicated that essentially all V antigenicity was removed. However, immunizations with pronase-treated V positive cells elicited V antibody production in one of two recipient cows. The numbers of antigens removed by different enzymes did not appear to be closely related to the amount of protein removed.
 ...
PMID:Removal of blood group determinants from bovine erythrocyte membranes. 3. Action of proteolytic enzymes on intact cells. 6 56

Antigenic properties of crystalline pepsin, trypsin and chymotrypsin were studied in 9 rabbits immunised with these enzymes. Production of antibodies and their titres were investigated by means of the reaction of the precipitation in testing tubes and immunoelectrophoresis. The most clear antigenic properties were revealed in trypsin, and they were the weakest in pepsin. Low titres of the antibody to pepsin were, probably, due to denaturation of its molecule at physiological values of pH immunisation. Absence of cross-reactions of antisera to trypsin and chymotrypsin with pepsin solutions may be due to considerable structural differences of the antigenic determinants of pepsin from those of trypsin and chemotrypsin. However, antisera to trypsin and chemotrypsin do develop cross-reactions with respective enzymes and there were may be due to a similarity between structures of their antigenic determinants.
 ...
PMID:[Antigenic properties of the proteolytic enzymes of the gastrointestinal tract]. 6 58

An antitryptic activity and effect of trypsin and chymotrypsin, administered parenterally, on the activity were studied in blood serum of patients, subjected to surgical operations. The antitryptic activity and content of alpha1- and alpha2-globulins were shown to increase in blood serum of patients within 5 days of the postoperative period. Intramuscular administration of the proteolytic enzymes within 5 days decreased the anti-tryptic activity and content of alpha1- and alpha2-globulins in blood serum.
 ...
PMID:[Effect of proteolytic enzymes on the antitrypsin activity of blood serum in the postoperative period]. 6 24

The time dependency of inactivation of human cationic trypsin and chymotrypsin II and of bovine trypsin and alpha-chymotrypsin by human serum has been investigated. Since the molar concentration of serum alpha1-proteinase inhibitor is much higher than that of other inhibitors, this time dependence could be used to calculate the rate constants kass for the association of alpha1-proteinase inhibitor with the four proteases. The association process was found to be second order, with kass ranging from 1 x10(4) s-1 (human trypsin) to 2.6 x 10(6) s-1 (bovine chymotrypsin). The human proteases react much more slowly with human alpha1-proteinase inhibitor than the bovine ones. But, whatever the species, chymotrypsin is inhibited more quickly than trypsin. Addition of alpha2-macroblobulin to the inactive complexes resulted in a time-dependent regeneration of enzymic activity due to the formation of alpha2-macroglobulin-protease complexes. The reactivation (i.e. dissociation) process was first order and extremely slow: the half-life of the alpha1-proteinase inhibitor-proteinase complexes ranged from 8 days (bovine chymotrypsin) to 9 months (human chymotrypsin). The human proteases formed the most stable complexes with alpha1-proteinase inhibitor. The pathological implications of these findings are discussed.
 ...
PMID:Kinetics of the inactivation of human and bovine trypsins and chymotrypsins by alpha1-proteinase inhibitor and of their reactivation by alpha2-macroglobulin. 6 11

Murine leukemia viruses, such as Rauscher leukemia virus (RLV), contain a proteolytic factor which becomes activated after detergent treatment of the virus. This factor specifically cleaves P70, the gag precursor polyprotein which is enriched for in preparations of immature virus core subparticles. The factor has been partially purified on Sephadex G-75 columns. It has a molecular weight of 10,000-12,000 daltons but does not coincide in elution position with the major peaks of the viral polypeptides p10 or p12. Under optimal conditions, that is 2% NP-40 (v/v), 10 mM DTT, (pH 7.2) and incubation for 16 hr at 22 degrees C, cleavage of labeled P70 occurs and increasing amounts of the four gag polypeptides p30, p15, p12 and p10 are obtained. The P70 cleavage activity is blocked by TLCK, TAME, CBZ-lysine and other lysyl-containing protease inhibitors. Further, the CBZ-lysine inhibition is reversible, while an inhibition by phenyl-methylsulfonyl fluoride (PMSF) is irreversible. These inhibition studies suggest that a similarity exists between the P70 proteolytic factor and some serine proteases, such as trypsin. The cleavage pattern of P70-rich immature cores treated with trypsin or chymotrypsin is different from that obtained with the P70 proteolytic factor. Thus murine leukemia virions apparently contain a unique, highly specific protease which is present in small amounts and cleaves P70.
 ...
PMID:Properties of a P70 proteolytic factor of murine leukemia viruses. 7 13

The effect of human skin proteases on vascular permeability and leukocyte emigration in rabbit skin was investigated. The alkaline protease of human skin capable of hydrolysing trypsin substrate effectively increased vascular permeability. This effect was not inhibited by antihistamine, but almost totally so by Trasylol. The reaction was protracted. Leukocyte emigration in skin, primarily of PMN-cells at 12 hrs, and later a migration of mononuclear cells, also resulted. Swelling of the dermal fibres was noted. The alkaline protease of human skin capable of hydrolysing chymotrypsin substrate also increased vascular permeability, but this phenomenon was effectively inhibited by antihistamine and the reaction was of brief duration. The leukocyte emigration caused by this enzyme was remarkable. The acid proteases of human skin resembling cathepsin B1 and D also caused brief increased vascular permeability, which was effectively inhibited by antihistamine. The cellular reactions to these acid proteases were mild. The role of protease inhibitors in skin in the enzyme reactions is discussed.
 ...
PMID:Human skin proteases: effect of separated proteases on vascular permeability and leukocyte emigration in skin. 7 4

Five protease inhibitors, I--V, in the molecular weight range 7000--8000 were purified from Tracy soybeans by ammonium sulfate precipitation, gel filtration on Sephadex G-100 and G-75, and column chromatography on DEAE-cellulose. In common with previously described trypsin inhibitors from legumes, I--V have a high content of half-cystine and lack tryptophan. By contrast with other legume inhibitors, inhibitor II contains 3 methionine residues. Isoelectric points range from 6.2 to 4.2 in order from inhibitor I to V. Molar ratios (inhibitor/enzyme) for 50% trypsin inhibition are I = 4.76, II = 1.32, III = 3.22, IV = 2.17, V = 0.97. Only V inhibit chymotrypsin significantly (molar ratio = 1.33 for 50% inhibition). The sequence of the first 16 N-terminal amino acid residued of inhibitor V is identical to that of the Bowman-Birk inhibitor; all other observations also indicate that inhibitor V and Bowman-Birk are identical. The first 20 N-terminal amino acid residues of inhibitor II show high homology to those of Bowman-Birk inhibitor, differing by 1 deletion and 5 substitutions. Immunological tests show that inhibitors I through IV are fully cross-reactive with each other but are distinct from inhibitor V.
 ...
PMID:Purification, partial characterization, and immunological relationships of multiple low molecular weight protease inhibitors of soybean. 7 87

Alpha2-M (alpha2-macroglobulin) was purified from human plasma by two different procedures. As well as having no detectable impurities by the usual criteria for testing the homogeneity of protein preparations, these alpha2M preparations showed a single component, after reduction in urea, of 185000 daltons by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The molecular weight of the alpha2M was found to be 718000 by sedimentation equilibrium experiments using the gravimetrically determined -v of 0.731 ml/g. The interaction of several proteinases with alpha2M was studied by using a novel discontinuous polyacrylamide-gel system, which showed clear separation of the enzyme-complexed alpha2M from the free alpha2M. These studies indicated that urokinase, as well as trypsin, chymotrypsin, plasmin and thrombin forms complexes with alphaM. The cleavage of the 185000-dalton subunit to a 85000-dalton species on interaction of trypsin with alpha2M was demonstrated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis after reduction of the alpha2M-trypsin complex in urea. The amino acid composition, carbohydrate content, absorption coefficient at 280 nm, the specific refractive increment and the sedimentation coefficient for these alpha2M preparations were measured. The stability of the trypsin-binding activity of the alpha2M preparations was also studied under several storage situations.
 ...
PMID:Physical and chemical properties of human plasma alpha2-macroglobulin. 8 Feb 17

An inhibitor of trypsin and chymotrypsin with apparent molecular weight of 68 000 and a mobility similar to alpha1-globulin on polyacrylamide gel electrophoresis, was isolated from serum-free supernatant preparations from HeLa cells. Immunoelectrophoresis assays indicated that the inhibitor differed serologically from known inhibitors of serine proteinases in plasma and urine but shared antigenic determinants with an unidentified protein in these body fluids and with an inhibitor recently isolated from cultures of lung.
 ...
PMID:Inhibitor of trypsin and chymotrypsin in cultures of HeLa cells. 8 Feb 30


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