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)

The effects of alimentary whey proteins given, as whole proteins (WP), controlled trypsin and chymotrypsin hydrolysate oligopeptides (WPH), or a free amino acid mixture (AAM), on growth, nitrogen retention, and steatorrhea were assessed in 24 Wistar rats (250 to 300 g) after 72 hr of starvation and 24 to 96 hr of realimentation and in 24 controls. The three diets had the same caloric, nitrogen, vitamin, and mineral contents. Rats had free access to the liquid diets. Only rats which ate the whole diet (90 cal) were included in the study. No differences in steatorrhea and fecal nitrogen were observed. The absorption rate was over 95% on the three diets. In contrast, weight gain was statistically better on WPH (+9% after 96 hr of realimentation) than on WP (+5%) or AAM (+2%). This was associated with a statistically higher nitrogen retention at all time periods studied, which was a result of a significant lower nitrogen urinary excretion. Similar results were obtained in controls. This better growth was a result of a better protein synthesis and lower ureagenesis.
...
PMID:Effect of whey proteins, their oligopeptide hydrolysates and free amino acid mixtures on growth and nitrogen retention in fed and starved rats. 277 42

Human cloned 35S-labeled NK cells were disrupted by nitrogen cavitation, and their secretory granules were obtained by filtration through 5-micron and 3-micron membrane filters followed by Percoll density-gradient centrifugation. These granule preparations, which contained 35S-labeled chondroitin sulfate A proteoglycans, were sonicated and were analyzed for carboxypeptidase activity and tryptic serine esterase activity. A carboxypeptidase activity that digested angiotensin I to des-Leu-angiotensin I, Ile-His-Pro-Phe to Ile-His-Pro and Phe, and hippuryl-L-phenylalanine to hippuric acid and Phe was detected in the granules of these NK cells. As determined by cleavage of the tetrapeptide, the pH optimum of the carboxypeptidase was 7.0. As assessed by the cleavage of N-benzyloxycarbonyl-L-lysine thiobenzyl ester (BLTe), the granule preparations also contained a serine esterase with trypsin-like specificity that had a pH optimum of 8.5. When the isolated secretory granules were disrupted and chromatographed on columns of Sepharose CL-2B in PBS, greater than 60% of the BLTe serine esterase activity and essentially all of the carboxypeptidase activity filtered as a macromolecular complex with approximately 8% of the 35S-labeled proteoglycans. Whereas treatment with 4 M urea or nonionic detergent failed to disrupt the macromolecular complex, the serine esterase activity was dissociated from the macromolecular complex in the presence of 3 M NaCl, demonstrating an ionic interaction with the proteoglycans. No difference was observed in the disaccharide composition of the chondroitin sulfate glycosaminoglycans of the 35S-labeled proteoglycans that were complexed with the enzymes as compared to those that were not complexed. These studies indicate that the secretory granules of human NK cells contain serine esterase activity and carboxypeptidase activity, both of which have neutral pH optima, and both of which are bound to protease-resistant chondroitin sulfate proteoglycans.
...
PMID:Identification of carboxypeptidase and tryptic esterase activities that are complexed to proteoglycans in the secretory granules of human cloned natural killer cells. 291 Oct 13

Cigarette smokers have an increased risk of chronic obstructive airways disease which has been attributed to a protease-antiprotease imbalance in the lung. The neutrophil is an important source of proteases as well as of myeloperoxidase, which oxidatively inactivates alpha-1-proteinase inhibitor (alpha-1-PI). The purpose of this study is to evaluate the protease-antiprotease imbalance hypothesis by measuring changes in peripheral blood components in a group of 110 young, male, asymptomatic smokers and an equal number of age-matched non-smokers. Significant (p = 0.001), but modest impairment of pulmonary function was observed in the smokers as measured by both forced expiratory spirometry and the single breath nitrogen test. A 35% increase (p = 0.0001) in peripheral blood leukocytes in smokers was attributable to increases in neutrophils (44%), lymphocytes (31%) and monocytes (23%). This increase in leukocyte count correlated significantly (p less than or equal to 0.01) with some of the more sensitive indicators of airway obstruction (FEV1/FVC, CV/VC, CC/TLC, and delta N2/L). Myeloperoxidase activity of neutrophils isolated from peripheral blood of smokers was 13% higher than in non-smokers, while elastase activity per neutrophil was apparently unaffected by smoking. In 50 subject pairs, elevations in serum alpha-1-PI concentrations in smokers (13.7%) were comparable to similar increases in trypsin (9.9%) and elastase (12.4%) inhibitory capacities. Expressed as nanomoles protease inhibited per nanomole of alpha-1-PI, the apparent functional activity of alpha-1-PI was unaltered by smoking. However, a lower, apparent functional activity of alpha-1-PI against trypsin and elastase was observed in both smokers and non-smokers with higher serum alpha-1-PI concentrations. Thus, in a population of young smokers, changes in leukocyte count, neutrophil lysosomal enzyme activities, and functional serum antiprotease activity appear to be consistent with the establishment of a protease-antiprotease imbalance. This imbalance may predispose these smokers to obstructive lung disease.
...
PMID:Effect of smoking on peripheral blood leukocytes and serum antiproteases. 299 5

Urinastatin, one of the trypsin inhibitors extracted from the human urine, has been reported to be useful in treating hypovolemic shock. We studied the effects of urinastatin on cardiac energy metabolism in acute hemorrhage in rats. The hemorrhage was produced by withdrawing blood (60 ml) from the abdominal aorta, and an equivalent volume of saline and 25,000 units/kg of urinastatin were injected over 5 min. The heart was then frozen quickly with liquid nitrogen, and high energy phosphates, lactate, pyruvate and glycogen contents were measured enzymatically. There was no significant difference in either ATP, lactate or pyruvate contents of the heart between the urinastatin-treated and the control groups. However, energy charge ([ATP + 0.5 X ADP]/[ATP + ADP + AMP]) and glycogen levels in the urinastatin-treated group were significantly higher than those in the control group. These findings suggest that urinastatin might produce a metabolic improvement in mitochondrial function and suppress the anaerobic glycogenolysis induced by circulatory deficiency in an acute hemorrhagic state.
...
PMID:Effects of urinastatin on cardiac energy metabolism in acute hemorrhage in rats. 302 12

The proteolytic activity of the intestinal bacterium Bacteroides fragilis NCDO 2217 was cell-bound during exponential growth, but was progressively released from the cells in stationary phase. Proteins hydrolysed included casein, trypsin, chymotrypsin, azocasein and the proteins in azosoya bean flour. Collagen, azocoll, elastin, gelatin, ovalbumin and bovine serum albumin were either weakly degraded or completely refractory to proteolysis. Arylamidase activity was exhibited against leucine p-nitroanilide (LPNA), leucine beta-naphthylamide, glycyl-proline p-nitroanilide and valyl-alanine p-nitroanilide. The bacterium grew with ammonia, peptone or casein as sole nitrogen source. Azocasein- and LPNA-hydrolysing activities were consistently higher when grown on casein. Cell-bound protease activity increased concomitantly with growth rate in both carbon- and nitrogen-limited continuous culture. Leucine arylamidase activity was also growth-rate-dependent, being 3-fold greater at D = 0.18 h-1 compared to D = 0.03 h-1. Extracellular proteolytic activity was only detected at low growth rates, accounting for about 25% of total protease activity.
...
PMID:Studies on the proteolytic activity of Bacteroides fragilis. 305 70

Certain cell-free filtrates from broth cultures of Pseudomonas aeruginosa, Hemophilus influenzae and Streptococcus pneumoniae stimulate secretion of glycoconjugates by explants of guinea pig trachea. The stimulatory effect is not related to toxicity or damage to the respiratory mucosa, as well as could be determined by ultrastructural examination of the explants after exposure. Bacteria isolated from patients with a history of chronic obstructive lung disease (P aeruginosa from cystic fibrosis, H influenzae, and S pneumoniae from chronic bronchitis) do not demonstrate increased frequency of positive strains or greater stimulation of secretion than organisms isolated from other individuals. At least three stimulatory substances are found in cell-free filtrates of P aeruginosa. They appear to be proteins of molecular weight 60,000-100,000 as determined by gel filtration. Within the crude filtrate, they are relatively stable to heat, proteolysis, and storage at 4 C and in liquid nitrogen. The stimulatory activity is not lost upon subculture of the bacteria. When isolated from the filtrate by column chromatography, they become labile to heat and trypsin. Isolated active fractions show proteolytic activity coinciding with mucin-stimulating capacity, suggesting a relationship with Pseudomonas proteases. Stimulatory substances released by S pneumoniae and H influenzae appear to be different from those elaborated by Pseudomonas. They are extremely labile to heat and storage, and the capacity to stimulate secretion is lost on subculture. Preliminary gel filtration indicates the S pneumoniae stimulatory substance(s) is in a molecular weight range of 100,000-300,000 daltons, while that of H influenzae is between 50,000 and 200,000. The results suggest bacteria which chronically infect or colonize respiratory airways of individuals suffering from obstructive lung disease can elaborate extracellular product(s) capable of stimulating secretion of mucin. Thus, the bacteria themselves may contribute to local manifestations and, ultimately, to the pathogenesis of obstructive disease.
...
PMID:Bacteria associated with obstructive pulmonary disease elaborate extracellular products that stimulate mucin secretion by explants of guinea pig airways. 309 81

Estramustine phosphate, an estradiol nitrogen-mustard derivative is a microtubule-associated protein (MAP)-binding microtubule inhibitor, used in the therapy of prostatic carcinoma. It was found to inhibit assembly and to induce disassembly of microtubules reconstituted from phosphocellulose-purified tubulin with either tau, microtubule-associated protein 2, or chymotrypsin-digested microtubule-associated protein 2. Estramustine phosphate also inhibited assembly of trypsin-treated microtubules, completely depleted of high-molecular-weight microtubule-associated proteins, but with their microtubule-binding fragment present. In all cases estramustine phosphate induced disassembly to about 50%, at a concentration of approximately 100 microM, at similar protein concentrations. However, estramustine phosphate did not affect dimethyl sulfoxide-induced assembly of phosphocellulose-purified tubulin. Estramustine phosphate is a reversible inhibitor, as the nonionic detergent Triton X-100 was found to counteract the inhibition in a concentration-dependent manner. The reversibility was nondisruptive, as Triton X-100 itself did not affect microtubule assembly, microtubule protein composition, or morphology. This new reversible MAPs-dependent inhibitor estramustine phosphate affects the tubulin assembly, induced by tau, as well as by the small tubulin-binding part of MAP2 with the same concentration dependency. This indicates that tau and the tubulin-binding part of MAP2, in addition to their assembly promoting functions also have binding site(s) for estramustine phosphate in common.
...
PMID:Effect of estramustine phosphate on the assembly of trypsin-treated microtubules and microtubules reconstituted from purified tubulin with either tau, MAP2, or the tubulin-binding fragment of MAP2. 311 77

Clostridium botulinum type G cultured for 6 days at 30 degrees C in proteose peptone-yeast extract-glucose medium produced toxin of 1.3 x 10(4) LD50/ml. The toxin was precipitated at pH 4.0, extracted with 0.2 M phosphate buffer, pH 6.0, and activated with trypsin. Sonic treatment and trypsinization of the residual precipitate released additional toxin, the toxicity of which corresponded to that detected in whole culture. Activated toxin obtained from the first extract and that from the residual precipitate were combined and purified by salting out, acid precipitation, gel filtration on Sephadex G-200, chromatography on SP-Sephadex, and a second gel filtration on Sephadex G-200. The yield of purified toxin from 10 liters of culture was 22.9 mg an 1.1 X 10(8) mouse ip LD50 with a specific toxicity of 3.0 X 10(7) mouse ip LD50/mg nitrogen. The molecular weight of the toxin was about 500,000, corresponding to that of L toxin of the other types. No M nor LL toxin was detected.
...
PMID:Purification of Clostridium botulinum type G progenitor toxin. 329 34

The protein deamidation process involves the conversion of the amide side-chain moieties of asparagine and glutamine residues to carboxyl groups. This conversion is an unusual form of protein modification in that it requires catalysis by an intramolecular reaction where both the substrate (asparagine and glutamine side chains) and "catalytic site" (the peptide nitrogen of the succeeding residue) are constituents of several consecutive residues along the polypeptide chain. The stereochemical factors governing this process were studied with a data base derived from the neutron crystallographic structure of trypsin from which amide groups and oxygen can be unambiguously differentiated because of their different neutron scattering properties. The neutron structure allowed for the direct determination of those residues that were deamidated; 3 of 13 asparagine residues were found to be modified. These modified residues were clearly distinguished by a distinct local conformation and hydrogen-bonding structure in contrast to those observed for the other asparagine residues. No correlation was found between preference to deamidate and the chemical character of residues flanking the site, as had been proposed from previous peptide studies.
...
PMID:Tertiary structure is a principal determinant to protein deamidation. 335 15

The present research was carried out for the purpose of collecting part of the germ plasm of grain amaranth in Guatemala, as well as to evaluate it in terms of yield, chemical composition and nutritive value. A total of 27 Guatemalan selections, one from Mexico and seven from Peru were planted in June 1982 in 7.5 m2 experimental plots replicated four times. The harvest seed was utilized for analysis of protein, ether extract, crude fiber, tannin content and trypsin inhibitors, as well as for NPR assays. A group of five pooled samples was made based on protein content for amino acid analyses; 10 samples were selected for a second NPR and protein digestibility assay. A preliminary assay on amino acid supplementation of raw grain flour is also reported. The selections were significantly different in grain yield. In general, selections which flowered at a short height and were harvested also at short height, tended to yield more seed. Findings revealed a negative relationship between plant height and grain yield, but a positive relationship between plant height and dry vegetable residue. Protein content of the grain averaged 15.0% with values ranging from 12.8 to 17.4%. Fat content varied from 5.6 to 10.6% with an average of 8.4%. Amaranth grain with a higher protein content contained greater amounts of amino acids on a weight basis, but when these were expressed on a nitrogen basis, differences disappeared. Based on the FAO/WHO amino acid reference pattern, grain amaranth protein was deficient in sulfur amino acids. Although the biological trial corroborated this deficiency, more studies should be undertaken. The NPR values of the samples from Peru averaged 2.30, the one from Mexico 2.04 and those from Guatemala, 2.36. Protein digestibility was 80, 82 and 74%, respectively. The data suggest that there is sufficient variability to select materials of a higher chemical composition, nutritive value, and yield.
...
PMID:The chemical composition and protein quality of amaranth grain germ plasm in Guatemala. 345 90


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

---