Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: HUMANGGP:036187 (gut)
 73,132 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The physical, chemical, and immunologic properties of a protease from rat skeletal muscle, proposed to function in the degradation of certain intracellular enzymes, are identical to those of a chymotrypsin-like serine protease isolated from peritoneal mast cells. The results of polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and 8 M urea indicate that the two rat proteases have identical mobilities corresponding to a molecular weight of 26,000. The relative amino acid compositions of the proteases are nearly identical. Immunodiffusion tests for crossreaction between the muscle protease and antisera directed toward mast cell protease indicate that the former is immunologically identical to mast cell protease. The first 35 amino-terminal residues of the two enzymes are identical and indicate homology of these proteins to other mammalian serine proteases. The sequence analysis of the protease from muscle was extended for an additional 16 positions, and comparison of this amino-terminal sequence with that of a similar enzyme from small intestine showed approximately 75% sequence identity. In contrast, only 40% of the residues in this region of bovine chymotrypsin A were found at corresponding loci in rat muscle protease. It is concluded that the protease from muscle or mast cells is closely related to the enzyme from small intestine which recently was localized in the "atypical" mast cells of gut mucosa [Woodbury, R. G., Gruzenski, G. M. & Lagunoff, D. (1978) Proc. Natl. Acad. Sci. USA 75, 2785-2789].
 ...
PMID:A major serine protease in rat skeletal muscle: evidence for its mast cell origin. 10 93

Culture filtrates of enteropathogenic strains of E. coli from adult patients with cholera-like diarrhoea produced a rhythm-disturbing effect when injected into isolated sacklets of rabbit ileum. This action was shown to be medium-dependant. It could not be elicited by cultures grown in synthetic medium. Meat extract cultures gave variable results, but the gut movements could be irritated regularly when cultures were grown in a casamino acids - yeast extract medium (table, figure). This activity which was not associated with non-pathogenic strains appeared in the beginning of the stationary phase of growth. The factor responsible for the dysrhythmic effect could be precipitated by ammonium sulphate, was dialysable, withstood boiling for 10 minutes (figure) and treatment with trypsin, chymotrypsin and pancreatin. Antisera prepared against culture filtrates of strain 10407 containing agglutinating and vascular permeability neutralizing antibodies did not neutralize the gut irritating effect efficiently. We conclude that the factor of our assay system is perhaps closely related to the heat-stable enterotoxin described by other authors concerned by E. coli enterotoxins.
 ...
PMID:[Toxin production by enteropathogenic colibacilli in adult persons (author's transl)]. 24 Nov 79

Crude preparations of hog gastric intrinsic factor or their own previously collected gastric juices administered with labeled vitamin B12 did not enhance vitamin B12 absorption in patients with vitamin B12 malabsorption secondary to pancreatic insufficiency. However, when these sources of gastric intrinsic factor were incubated with three times crystallized preparations of insolubilized bovine trypsin or chymotrypsin, the proteolytic enzymes were removed by centrifugation, and the preparations of gastric intrinsic factor were readministered to these patients, the absorption of vitamin B12 was markedly enhanced. Studies of hog gastric intrinsic factor before and after exposure to proteolytic enzymes failed to show any difference on Sephadex chromatography or polyacrylamide gel electrophoresis or on its affinity for vitamin B12 or the ileal receptor in guinea pigs. These investigations demonstrate that: (1) gastric intrinsic factor as secreted by subjects with pancreatic insufficiency or obtained from hog pyloric mucosal extracts is ineffective in promoting vitamin B12 absorption in patients with pancreatic insufficiency, (2) incubation of crude preparations of gastric intrinsic factor with insolubilized pancreatic proteases modified these preparations of gastric intrinsic factor in an as yet undefined manner, allowing them to enhance vitamin B12 absorption, and (3) in vitro studies using gut sacs or brush border preparations do not reflect the abnormality in vitamin B12 absorption associated with pancreatic dysfunction.
 ...
PMID:Evidence that pancreatic proteases enhance vitamin B12 absorption by acting on curde preparations of hog gastric intrinsic factor and human gastric juice. 31 82

1. The food intake, pancreas weight and trypsin (EC 3.4.21.4) and alpha-chymotrypsin (EC 3.4.21.1) activities in the pancreas were measured in rats during pregnancy and lactation and after the young were weaned. 2. All the quantities measured increased significantly during lactation and had returned to their original values by 4 weeks after weaning. Food intake and pancreas weight were highest after the second week of lactation. Total trypsin and alpha-chymotrypsin activity, and the activity per g tissue, fell during pregnancy and rose during lactation, reaching a maximum 1 week after weaning. 3. From these and other results it is suggested that the hypertrophy and hypersecretion of pregnancy and lactation are initiated by changes insulin secretion and mediated by the trophic effects of gut hormones, and that differences in the nature and timing of the response may be controlled by nutrient availability.
 ...
PMID:The effects of pregnancy and lactation on the activities of trypsin and alpha-chymotrypsin in the rat pancreas. 46 45

Rats were fed a heat damaged casein (autoclaved 24 hours, 121 degrees, 2 atm) diet to determine the effect of poorly digested protein on pancreatic enzyme levels and response to a meal. After 10 days of feeding, the pancreas showed no signs of atrophy, however, chymotrypsin and amylase activities were lower in proportion to body weight. An estimation of secretion during the meal was similar or slightly lower in rats fed heated casein (HC) as compared to the casein diet (C), but a greater levels of enzyme activity was found in the intestinal contents of rats fed HC relative to control rats. These results suggest that the turnover of enzymes in the gut is reduced when a less digestible protein is fed, and that the endogenous pancreatic secretions and the dietary protein are not digested and absorbed as well.
 ...
PMID:Long term pancreatic response to feeding heat damaged casein in rats. 47 54

The digestion and absorption of collagen, native and artificially cross-linked, has been examined in the rat and the Gaboon viper, by feeding known quantities and measuring the hydroxy-proline content of the faeces and of the contents of the gut at different levels, and comparing with an unabsorbable marker (polyethylene glycol). Incubation of collagen in vitro with pepsin at 37 degrees C at pH 1.5 followed by trypsin or chymotrypsin converted about 40% into dialysable material.
 ...
PMID:Digestion of native collagen in the gut. 63 45

Changes in the activities of three gastric and nine pancreatic enzymes plus colipase were determined during postnatal development and weaning in calves. In calves exclusively milk-fed for 2, 7, 28, 56, 70 and 119 d, the enzyme activities per kilogram of empty live weight increased with age for chymotrypsin, elastase, carboxypeptidases A and B, ribonuclease and alpha-amylase, decreased for chymosin, lysozyme and colipase but showed no change in the case of pepsin, trypsin, lipase and phospholipase A2 compared with animals at birth. The greatest increase was that in alpha-amylase activity (about 50-fold between d 2 and 119). In calves weaned between d 28 and 56, all the activities were higher than in milk-fed animals, except that of chymosin (which was slightly lower) and that of colipase (which did not change). At 119 d of age, chymotrypsin, carboxypeptidase A, alpha-amylase and lipase were 1.6- to fourfold higher in ruminants than in preruminants. Thus, most enzyme activities were modified first by colostrum and milk intake, and again upon weaning by development of the forestomachs and ingestion of solid food. These ontogenic patterns might be under the control of many gut regulatory peptides, the plasma concentrations of which changed simultaneously. Some gastric and pancreatic enzymes were correlated to plasma concentrations of these gut regulatory peptides.
 ...
PMID:Gastric and pancreatic enzyme activities and their relationship with some gut regulatory peptides during postnatal development and weaning in calves. 137 46

Proteinases and peptidases from the intestinal tract of fifth-instar larvae of Heliothis (= Helicoverpa) zea (Boddie) (Lepidoptera:Noctuidae) were characterized based on their substrate specificity, tissue of origin, and pH optimum. Activity corresponding to trypsin, chymotrypsin, carboxypeptidases A and B, and leucine aminopeptidase was detected in regurgitated fluids, midgut contents, and midgut wall. High levels of proteinase activity were detected in whole midgut homogenates, with much lower levels being observed in foregut and salivary gland homogenates. In addition, enzyme levels were determined from midgut lumen contents, midgut wall homogenates, and regurgitated fluids. Proteinase activities were highest in the regurgitated fluids and midgut lumen contents, with the exception of leucine aminopeptidase activity, which was found primarily in the midgut wall. Larvae fed their natural diet of soybean leaves had digestive proteinase levels that were similar to those of larvae fed artificial diet. No major differences in midgut proteinase activity were detected between larvae reared under axenic or xenic conditions, indicating that the larvae are capable of digesting proteins in the absence of gut microorganisms. The effect of pH on the activity of each proteinase was studied. The pH optima for the major proteinases were determined to be pH 8.0-8.5 for trypsin, when tosyl-L-arginine methyl ester was used as the substrate; and pH 7.5-8.0 for chymotrypsin, when benzoyl-L-tyrosine ethyl ester was used as the substrate.
 ...
PMID:Digestive proteinases of larvae of the corn earworm, Heliothis zea: characterization, distribution, and dietary relationships. 179 75

Oral inoculation of suckling mice with reovirus serotype 1 (strain Lang) results in the conversion of intact virions to intermediate subviral particles (ISVPs) in the intestinal lumen. Digestion of virus in vitro with chymotrypsin or trypsin reveals two distinct forms of ISVPs, while the predominant species of ISVPs found in the small intestinal lumen appears to be identical to the chymotrypsin product. The in vivo conversion of virions to ISVPs was blocked by pretreatment of mice with protease inhibitors, resulting in inefficient replication of reovirus in intestinal tissue. The early inhibition of viral replication in suckling mice pretreated with protease inhibitors was not observed when suckling mice were inoculated with ISVPs generated by in vitro digestion with either chymotrypsin or trypsin. However, replication was decreased during secondary rounds of replication in mice receiving repeated doses of protease inhibitors, suggesting that luminal proteolytic digestion is important in rendering progeny virions infectious in the gut.
 ...
PMID:Intraluminal proteolytic activation plays an important role in replication of type 1 reovirus in the intestines of neonatal mice. 215 65

We have isolated a clustered gene family in D. melanogaster that codes for trypsin-like enzymes. The gene family has been localized to 47D-F by in situ hybridization to polytene chromosomes. The four genes in the family are transcribed in alternating orientations, and code for 1000 nt mRNAs. Transcripts are present at all stages of the life cycle. In situ hybridization to mRNA in tissue sections of third instar larvae showed that transcripts were restricted to the mid-gut. One gene was sequenced. The translated amino acid sequence of the proposed active enzyme is 42% homologous to bovine trypsin. Regions of functional importance are more strongly conserved. These include the active site residues asp102, his57, ser195, and the residue asp189 which is reputed to bind the basic residue at the substrate cleavage site. The activation peptide is not homologous to that of most vertebrate trypsins, suggesting a modified activation mechanism. The sequence further strengthens the hypothesis that the chymotrypsin cleavage specificity developed separately in the vertebrates and invertebrates.
 ...
PMID:A gene family in Drosophila melanogaster coding for trypsin-like enzymes. 241 27


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