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:3.2.1.20 (
alpha-glucosidase
)
4,237
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The activity of the membrane-bound enzymes of the microvillous zone of the entreocytes (
maltase
, sucrase, trehalase, lactase, cellobiase, alkaline phosphatase and leucylaminopeptidase) was studied in mucosal smears from the proximal jejunum, ileum, caecum and sigmoid flexure in a group of control (C) (8) and germ-free (GF) (7) rabbits. The trypsin and
chymotrypsin
activity of the contents of the ileum, caecum and sigmoid flexure was studied in 6 C, 5 GF and 5 monocontaminated (MC) rabbits. In summing up it can be stated that the individual membrane-bound enzymes have a different gradient in the various intestinal segments of C and GF rabbits and that they differ reciprocally in character. The maximum statistically significant differences between GF and C rabbits were found in the ileum; in the jejunum they were somewhat smaller and in the caecum smaller still (in this localization the difference was C versus GF). Striking differences in the proportion of the individual disaccharidases were found inthe jejunum and ileum of C rabbits compared with GF rabbits, in which, in both these segments of small intestine the relationship
maltase
greater than sucrase greater than trehalase greater than lactase was preserved. The proteolytic activity of the intestinal contents likewise had a different gradient character in C, MC and GF rabbits. The maximum activities (especially trypsin) were found in MC animals. The microbial flora is one of the factors regulating the enzymatic activities of the microvillous zone of the enterocytes and it also significantly influences the proteolytic activity of the intestinal contents. This influence is particularly marked in the distal part of the alimentary tube.
...
PMID:Digestive enzymes of the mucosa of the small intestine and trypsin and chymotrypsin proteolytic activity of the intestinal contents of germ-free, monocontaminated and conventional rabbits. 35 55
Bacterial extracts were prepared from cultures originating in chronic self-filling intestinal blind loops in rats. Their ability to remove active
maltase
molecules from isolated brush border membranes was studied in vitro. Twelve strains in 51 tested, belonging to one of three species, Bacteroides fragilis, Clostridium perfringens, and Streptococcus fecalis, possessed
maltase
-releasing activity. The ability to remove
maltase
correlated well with the ability to hydrolyze p-nitrophenyl-tert-butyloxycarbonyl-l-alaninate (NBA), an ester substrate rapidly hydrolyzed by elastase, but not with substrated favored by tryhsin and
chymotrypsin
. Maltase-releasing activity from C. perfringens was strongly inhibited by soybean trypsin inhibitor and to a lesser extent by lima bean trypsin inhibitor. Of four chloromethylketone active-site directed inhibitors tested with specificities for elastase, trypsin, and
chymotrypsin
, inhibition was maximal with elastase-specific inhibitors. In two species, activity was shown to be heat sensitive, and to be inhibited by concentration of the extract. In one species
maltase
-releasing activity was shown to be due to an enzyme of molecular weight at least 66,000 with the capacity to remove lactase, sucrase, and alkaline phosphatase, as well as
maltase
. The results indicate that anaerobic or facultatively anaerobic species, previously identified with the pathology of of the blind loop syndrome, contain proteases which are capable of removing components of the intestinal surface membrane. These proteases appear to have elastase-like substrate specificity and may be involved in the etiology of disaccharidase deficiency in bacterial overgrowth syndromes.
...
PMID:Pathogenesis of mucosal injury in the blind loop syndrome. 35
At 20 degrees C, aflatoxin B1, at a sublethal dose, decreases the activity of alkaline phosphatase (EC 3.1.3.1),
alpha-glucosidase
(
EC 3.2.1.20
), esterase (EC 3.1.1.1),
chymotrypsin
(EC 3.4.21.1), leucine aminopeptidase (EC 3.4.11.1), and phosphoamidase (EC 3.9.1.1) biosynthesis in Bacillus thuringiensis (Berliner). In contrast, at 41 degrees C no significant decrease was observed. At this temperature, the mycotoxin is not destroyed or metabolized and bacterial cells are resistant to the toxin.
...
PMID:[Effect of aflatoxin B1 on the enzymatic activities of Bacillus thuringiensis (Berliner)]. 88 28
The releases of proteins,
maltase
, lactase, sucrase, trehalase, alkaline phosphatase, gamma-glutamyltransferase and leucylnaphthylamide-hydrolyzing activity from human intestinal brush bborder membrane vesicles by various enzymes (especially pancreatic proteases) have been studied. The brush border membrane enzymes are not solubilized by digestion with trypsin and
chymotrypsin
but are largely released after treatment with papain or elastase. Most of the enzymes are fully active after the proteolytic treatment. All proteins released by papain and elastase have been identified by electrophoresis to already known intestinal hydrolases. Electron microscopy of brush border membrane vesicles demonstrates "knob-like" structures (particles) attached to the external side of the membrane. During papain treatment, enzyme removal runs parallel with the disappearance of the particles. During elastase treatment it is not possible to correlate the release of the enzymic activities with the removal of the particles. The results indicate that most of the intestinal hydrolases are surface components attached to the external side of the membrane. They are in accord with the concept that the brush border membrane enzymes are organized within the membrane in a mosaic-like pattern.
...
PMID:Enzymic solubilization of the human intestinal brush border membrane enzymes. 127 90
1. The role of endogenous CCK in the development of digestive enzyme activities in small intestine and pancreas was investigated in suckling rats. Synthetic protease inhibitor (camostat 100 micrograms/g bwt) was orally administered twice daily for 5 days from 11 days of age. 2. Pancreatic hypertrophy and hyperplasia, and alteration of pancreatic enzyme composition, especially decreases in amylase activity and increases in trypsin and
chymotrypsin
activities were produced by camostat treatment. These changes were completely suppressed by simultaneous administration of the potent CCK receptor antagonist L-364,718 (1 microgram/g bwt). 3. With camostat treatment, intestinal lactase activity decreased to 41%, while
maltase
and sucrase activities increased 3 and 2.5 times respectively. These changes in enzyme activities were not affected by the application of L-364,718. 4. The mucosal disaccharidase and pancreatic enzyme activities could not be modified by chronic subcutaneous injection of camostat. The precocious induction of
maltase
and sucrase activities by camostat treatment was also observed in the adrenalectomized pups. 5. These results indicate that pancreatic growth accompanied by alteration of digestive enzyme composition in the suckling rats is regulated by endogenous CCK, but the precocious induction of disaccharidase activities is not mediated by endogenous CCK released by camostat treatment.
...
PMID:Precocious alteration of digestive enzyme activities in small intestine and pancreas by chronic oral administration of protease inhibitor in suckling rats. 168 62
Organ weights and digestive enzyme contents of the pancreas, stomach and duodenum were measured in 75 nursing piglets at 21 d of age. Piglets were given creep feed from 10 d of age. Creep feed intake was less than 1.5 g.d-1.piglet-1 up to d 18; on d 19 and 20 it averaged 15 g.d-1.piglet-1. On d 10, piglets went to the feeder more frequently than on the following days. Feeding bouts were longer on d 16, 17 and 18 just prior to the increase in creep feed consumption. Means and SE for the parameters studied at 21 d of age were 7.01 +/- .18 mg for pancreas weight; 61,499 +/- 4,091 units of amylase (UA) and 1,510 +/- 110 UA/mg DNA; 2,962 +/- 189 units of
chymotrypsin
(UC) and 68.94 +/- 3.92 UC/mg DNA; 8.76 +/- .35 g for fundic mucosa weight; 558,875 +/- 49,287 units of pepsin (UP) and 12,338 +/- 1,175 UP/mg DNA; 1.75 +/- .06 g for duodenum weight; 1.39 +/- .07 units of
maltase
(UM) and .14 +/- .006 UM/mg DNA. Day-0 weight was not correlated with 21-d gain. Feeding behaviors were correlated positively with 21-d gains. Feeding behaviors and behaviors were correlated positively to pancreas total and specific enzyme contents as well as to stomach and duodenum weights, RNA/DNA ratios of the pancreas and the stomach and protein/DNA of the pancreas but were correlated negatively with specific and total pepsin and
maltase
activities. Variation was large in enzyme activities (cv = 35 to 82%).(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Relationships of weight gain and behavior to digestive organ weight and enzyme activities in piglets. 248 Mar 40
Dietary fibres (Plantago ovata seeds, P. ovata husks, wheat bran, alfalfa, pectin, xylan) were incubated in vitro with gastrointestinal enzymes (pepsin, trypsin,
chymotrypsin
, lipase, alpha-amylase,
maltase
, lactase) in buffer solutions at concentrations of 1-5% for 10-30 min at 37 degrees C. All fibres induced sometimes pronounced changes in enzyme activity, but the effect of the different fibres on the various enzymes varied individually and was not predictable. Both P. ovata preparations had no (pepsin, trypsin, alpha-amylase) or only stimulating (
chymotrypsin
, lipase, lactase) actions whereas all other fibres showed inhibiting as well as stimulating influences. Wheat bran induced the most pronounced alterations increasing lipase,
maltase
and lactase activity and inhibiting alpha-amylase activity. Pectin and xylan were comparable in decreasing lipase and pepsin activity and in increasing
chymotrypsin
activity but had opposite effects on
maltase
activity. Alfalfa was able to stimulate lactase and lipase activity but depressed trypsin and alpha-amylase activity. The inactivation of enzymes by dietary fibres can, at least partly, be explained by adsorption to the fibre or by the presence of enzyme inhibitors especially in natural compounds. The reasons for activation processes are unknown. As enzyme activities are decisive for food digestion, the properties of the individual fibres should be carefully considered when used as dietary supplement in physiological or pathological conditions.
...
PMID:Interference of dietary fibres with gastrointestinal enzymes in vitro. 248 92
Intestinal and pancreatic enzyme activities are known to respond to changes in dietary composition. Studies in rats and humans suggest that adaptive mechanisms differ between species in response to altered intakes of carbohydrate and fat. Because of increased use of the pig in the study of human nutrition, we compared the responses of pancreatic enzymes and intestinal disaccharidases in groups of 7- to 10-week-old pigs fed either high-carbohydrate/low-fat (70 cal% starch, 25% protein, 5% fat) or low-carbohydrate/high-fat (5, 25, 70%, respectively) diets for 7 and 30 days. No changes were observed in the activities for lactase, trypsin, or
chymotrypsin
or in the tissue protein concentrations, regardless of diet duration. High-carbohydrate/low-fat intake resulted in higher specific activities of sucrase,
maltase
, and amylase for both periods studied. Low-carbohydrate/high-fat intake resulted in higher specific activities of pancreatic lipase for both periods studied. The response of the intestinal disaccharidases differs from that observed previously in rodents but resembles the response reported in humans. Conversely, amylase and lipase responded similarly to the pattern in the rat. These data support the continued use of the pig as a suitable model in the study of adaptation to altered intakes of carbohydrate and fat.
...
PMID:Effect of diet on intestinal and pancreatic enzyme activities in the pig. 319 78
The enzymatic activities of 53 strains of Pseudomonas cepacia were determined by using the API ZYM system. Strong alkaline phosphatase, acid phosphatase, butyrate esterase, caprylate esterase, myristate lipase, leucine arylamidase, and phosphoamidase activities were consistently detected in all strains. Weak activities were observed for valine arylamidase, beta-glucosidase, and N-acetyl-beta-glucosaminidase. No activities could be demonstrated for cystine arylamidase, trypsin,
chymotrypsin
, alpha-galactosidase, beta-galactosidase, beta-glucuronidase,
alpha-glucosidase
, alpha-mannosidase, and alpha-fucosidase. Enzymatic activities of pseudomonads may provide useful information about their pathogenesis and information for identification of Pseudomonas species.
...
PMID:Enzymatic characterization of Pseudomonas cepacia by API ZYM profile. 335 98
Five Beagle dogs, equipped with duodenal and gastric fistulae, were fed a standard diet before receiving the same diet supplemented with wheat bran for 1 month. Pancreatic secretory investigations performed in conscious animals before and 1 month after bran administration showed a significant parallel increase in the flow rate of pancreatic secretion and the outputs of bicarbonate and amylase both in basal and secretin-stimulated conditions. The outputs of protein and
chymotrypsin
increased only in unstimulated secretions, while the output of lipase was strongly reduced in response to secretin. However, the small intestinal mucosa was not affected by bran administration. Dietary fiber did not alter the height of the villi or the activity of sucrase,
maltase
and aminopeptidase in mucosal homogenates or isolated brush border membranes from intestinal biopsies. These data suggest that wheat bran supplemented to the standard diet affects the exocrine pancreatic secretion but not intestinal enzyme activities involved in the absorption of carbohydrates and proteins in the dog.
...
PMID:Effects of wheat bran on the exocrine pancreas and the small intestinal mucosa in the dog. 620 61
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