Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.20 (alpha-glucosidase)
 4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mycelial and yeast forms of P. brasiliensis were tested for several glucohydrolases. In addition to high levels of beta-glucanases, low amounts of alpha-glucanase, chitinase and maltase were found. Tests for invertase, amylase and lactase were negative. The levels of beta-1,3-glucanase were higher in the mycelial form. The shift to the mycelial phase correlated with an increase in the levels of beta-1,3-glucanase. The enzyme was present in the cytoplasm, cell wall and culture medium. The extracellular enzyme was purified 42 fold by ammonium sulphate precipitation and gel filtration. Maximal activity was obtained at 60 degrees C and pH of 5.0 (acetate buffer or pH 6.0 (phosphate buffer). Its Km was 0.205 mg/ml. The cell wall-bound enzyme showed a higher temperature optimum. Optimum pH and Km were also slightly different. Following treatment of the cell walls with chitinase, beta-1,3-glucanase was released into the medium.
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PMID:Beta-1-3-glucanase and dimorphism in Paracoccidioides brasiliensis. 4 May 30

Enzymes capable of hydrolyzing cell walls of Blastomyces dermatitidis and chemotypes I and II of Histoplasma capsulatum were prepared in the laboratory or obtained from commercial sources. They included chitinases, beta-1,3-glucanases, beta-1,6-glucanase, and Pronase. Monosaccharides and disaccharides of glucose released from the cell walls by the enzymes were determined qualitatively by paper and gas-liquid chromatography, and monosaccharides were quantitated by the latter technique as well. An enzyme system isolated from Streptomyces sp. containing both chitinase and glucanase released maximum amounts of glucose and N-acetylglucosamine from the cell walls of H. capsulatum chemotype I. A chitinase preparation, free of glucanase, from Serratia marcescens released only chitobiose and N-acetylglucosamine from chemotype I cell walls, but the total quantity of N-acetylglucosamine released was about 60% less than that released by the Streptomyces system. A beta-1,3-glucanase from Bacillus circulans hydrolyzed the cell walls of H. capsulatum chemotype I, but a beta-1,6-glucanase failed to release glucose from the same walls. Autolytic enzymes, viz., beta-1,3-glucanases and several glycosidases were detected as constitutive enzymes in both yeast and mycelial phases of B. dermatitidis and H. capsulatum chemotypes I and II. No difference in the amount of activity was found between cell sap and culture filtrate preparations. The beta-glucanases prepared from the Histoplasma and Blastomyces strains were active on the cell walls of the yeast phases of H. capsulatum chemotypes I and II, releasing laminaribiose and glucose, but were essentially inactive on the cell walls of B. dermatitidis. Chitinase, beta-1,6-glucanase, alpha-glucanase, and alpha-glucosidase activities were absent from these fungal enzyme preparations.
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PMID:Cell wall studies of Histoplasma capsulatum and Blastomyces dermatitidis using autologous and heterologous enzymes. 87 Apr 37

This is a summary of the recent work on some glycosidases of sand flies and their Leishmania parasites. Glycosidases catalyze the hydrolysis of complex sugar subunits of polysaccharides into simple sugars. Leishmania major parasites secrete chitinase and N-acetylglucosaminase, which enables them to survive in the gut of the sand fly and are important in facilitating their transmission by the phlebotomine sand fly Phlebotomus papatasi. These enzymes are found in a wide range of trypanosomatids and the gene locus is highly conserved. The sand flies feed on plants and the ingested tissues may contain cellulose particles that the sand flies are unable to digest. Cellulolytic enzymes are secreted by L. major promastigotes and this may help to break down cellulose in infected flies and sustain their growth. Starch is a main photosynthesis product that is stored in leaves. Starch grains have been found in the midguts of field caught sand flies and alpha-amylase, the specific enzyme for starch, has been found in the salivary glands and other organs of Lutzomyia longipalpis and P. papatasi. Alpha-amylase and alpha-glucosidase are expressed by L. major promastigotes and alpha-glucosidase is secreted by several trypanosomatid genera, but not by all those examined. Primers originally designed to amplify P. papatasi amylase DNA sequences, by polymerase chain reaction (PCR), also amplified DNA from all Old World Leishmania species, indicating that the gene is highly conserved between sand flies and these parasites.
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PMID:The biological function of sand fly and Leishmania glycosidases. 1177 Jan 10

Fluorogenic artificial substrates facilitate sensitive enzyme activity measurements for a variety of processes in soil and other environmental samples. It is possible to use in situ pH for measurements on condition that the substrates are chemically stable. We studied the stability of 12 different methyl umbellipherone (MUF) and amino methyl coumarine (AMC) derivatives used as substrates for arylsulphatase, alpha-glucosidase, beta-glucosidase, beta-xylosidase, cellobiosidase, chitinase, phosphomonoesterase (PME), phoshodiesterase (PDE), esterase, lipase and alanine- and leucine aminopeptidases (AP) over the pH range from 4.0 to 8.0 in modified universal buffer (MUB). Stability of the substrates for lipase (4-MUF-heptanoate) and esterase (4-MUF-acetate) measurements was poor, especially at the higher pH values. Chitinase substrate, 4-MUF-N-acetyl-beta-D-glucosamide, was unstable at high pH values whereas the substrate for PME activity measurement (4-MUF-phosphate) disintegrated at low pH. The other substrates and MUF and AMC standard solutions were stable over the pH range studied. The optima between pH 4 and 8 of the 11 different enzyme activities were measured in three forest and two agricultural soil samples and in one activated sludge sample. In soil, for alanine and leucine AP the pH optima were usually 7.5 or higher, for arylsulphatase, beta-glucosidase, beta-xylosidase, esterase and PDE between 4 and 5.5, and for cellobiosidase between 4 and 5. alpha-Glucosidase had an optimum below 5.5 but also exhibited high activity at pH 7. Soil-dependent variation in pH optima were observed for chitinase, esterase, PDE and PME. Enzyme activities were also measured in 0.5 M acetate buffer at pH 5.5. This buffer yielded the highest activities in all soil samples for arylsulphatase, PDE and PME.
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PMID:Stability of the fluorogenic enzyme substrates and pH optima of enzyme activities in different Finnish soils. 1559 94

The digestive physiology and stomach contents of six crab species from a variety of habitats were investigated to provide an indication of their digestive capability and dietary preferences. Stomach contents varied between species, but the key enzymes present were generally consistent with the types of dietary material being ingested. Nectocarcinus integrifons (red rock crab) consumed large quantities of seagrass and had high cellulase activity (0.02+/-0.004 units mg-1) to digest the constituent cellulose. Petrolisthes elongatus (porcelain crab) ingested brown and green phytoplankton and algae and had considerable laminarinase (0.35+/-0.08 units mg-1) and beta-glucosidase (0.025+/-0.005 units mg-1) activities to digest the laminarin in its diet. Leptograpsus variegatus (omnivorous swift-footed shore crab) had high activities of protease (1.2+/-0.02 units mg-1), alpha-glucosidase, and alpha-amylase and appeared well equipped to utilize both dietary protein and carbohydrate. Stomach contents in Nectocarcinus tuberculosus (velvet crab) and Carcinus maenas (green crab) also suggest that these species are omnivorous. N. tuberculosus had high cellulase and chitinase for digesting the cellulose in plants and the chitin in invertebrate shells respectively. C. maenas had intermediate digestive enzyme levels and may employ more of a generalist feeding strategy than other species. Plagusia chabrus (speedy crab) is carnivorous, consuming encrusting bryozoans, hydroids, crustaceans, and fish. It has high protease activity, particularly trypsin (0.73+/-0.12 units mg-1), to digest the protein in its animal prey. Each species of crab studied had a complex suite of digestive enzymes, the relative activities of which reflected individual and very different species-specific dietary niches.
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PMID:Dietary preference and digestive enzyme activities as indicators of trophic resource utilization by six species of crab. 1571 11

We examined seasonal and age-related variation in digestive organ sizes and enzyme activities in female western sandpipers (Calidris mauri) refueling at a coastal stopover site in southern British Columbia. Adult sandpipers exhibited seasonal variation in pancreatic and intestinal enzyme activities but not in digestive system or organ sizes. Spring migrants had 22% higher total and 67% higher standardized pancreatic lipase activities but 37% lower total pancreatic amylase activity than fall migrants, which suggests that the spring diet was enriched with lipids but low in glycogen. Spring migrants also had 47% higher total intestinal maltase activity as well as 56% higher standardized maltase and 13% higher standardized aminopeptidase-N activities. Spring migrants had higher total enzymic capacity than fall migrants, due primarily to higher total lipase and maltase activities. During fall migration, the juvenile's digestive system was 10% larger than the adult's, and it was composed differently: juveniles had a 16% larger small intestine but a 27% smaller proventriculus. The juvenile's larger digestive system was associated with lower total enzymic capacity than the adult's due to 20% lower total chitinase and 23% lower total lipase activities. These results suggest that juvenile western sandpipers may process food differently from adults and/or have a lower-quality diet.
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PMID:Digestive organ sizes and enzyme activities of refueling western sandpipers (Calidris mauri): contrasting effects of season and age. 1588 90

Membrane barriers which prevent direct contact between Fusarium solani and pea endocarp tissue prevent fungal spores from inducing phytoalexin production. Conversely, preinduced host resistance responses are not readily transported from the plant across the membrane barrier to Fusarium macroconidia.Crude enzyme extracts from pea endocarp tissues partially degrade Fusarium solani f. sp. phaseoli cell walls. Activities of the glycosidic enzymes, chitinase, beta-1,3-glucanase, chitosanase, beta-D-N-acetylglucosaminidase, beta-D-N-acetylgalactosaminidase, beta-D-glucosidase, alpha-D-glucosidase, and alpha-D-mannosidase, were detected in pea endocarp tissue. If pods are challenged with Fusarium spores or chitosan, the chitinase activity of the infected tissue remains higher than water-treated pods 0.5 to 6 hours after treatment. The beta-1,3-glucanase activity increases within 6 hours in both inoculated and control tissue. Chitosanase activity was lower in tissue treated with Fusarium solani f. sp. pisi, f. sp. phaseoli or chitosan than in water-treated control tissue. Thus, the pea tissue contains glycosidic enzymes with the potential to degrade the major compounds of the Fusarium cell walls.
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PMID:Glycosidic Enzyme Activity in Pea Tissue and Pea-Fusarium solani Interactions. 1666 4

The digestive physiology and biochemistry of larvae of the leaf-cutting ant Acromyrmex subterraneus were investigated here. The activity of digestive enzymes was evaluated in the labial glands, midgut epithelium (soluble and particulate fractions), and in the lumen contents, separated into endo and ectoperitrophic regions. Enzymes with high levels of activity were partially characterised using chromatography and electrophoresis techniques. Microscope observations were carried out and the anatomy of the larval digestive tract was described here for the first time. Larvae fed with pH indicator solutions showed the anterior portion of the midgut to be acidic and the posterior portion neutral to alkaline, indicating that the pH of the different regions of the midgut could optimise certain enzyme activities, whilst inhibiting others. The flow rate of the intestinal contents was also evaluated in larvae fed with a dye solution. The slow flow rate is probably due to closure of the rear end of the larval midgut. No compartmentalisation of digestive enzymes acting on oligosaccharides and disaccharides in the ectoperitrophic space and on polysaccharides in the endoperitrophic space was observed here, which could also be related to the closure of the midgut. The digestive physiology of these larvae is therefore similar to ancestral Holometabola, a paradox when considering the highly evolved nature of these insects. The larval midgut demonstrated a large diversity of enzyme activities with high levels of alpha-amylase, alpha-mannosidase, chitinase, alpha-glucosidase, beta-glucosidase and proteinase. High levels of chitinase and amylase activities were detected in the labial glands of larvae. The enzyme profile reflected the necessity of the larvae to degrade the fungal substrate, their sole diet, and a probable source of some of the digestive enzymes detected here. When compared to adults, the larvae had a greater diversity and higher levels of enzyme activity, highlighting their importance as the "digestive caste" of the colony.
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PMID:Digestive enzymes in larvae of the leaf cutting ant, Acromyrmex subterraneus (Hymenoptera: Formicidae: Attini). 1768 27

A new polyhydroxylated pyrrolizidine alkaloid designated as pochonicine (1) was isolated from a solid fermentation culture of the fungal strain Pochonia suchlasporia var. suchlasporia TAMA 87. The structure of 1 was determined using NMR and MS techniques as (1R*, 3S*, 5S*, 6S*, 7R*, 7a S*)-5-acetamidomethyl-3-hydroxymethyl-1,6,7-trihydroxypyrrolizidine. Pochonicine (1) showed potent inhibition against beta-N-acetylglucosaminidases (GlcNAcases) of various organisms including insects, fungi, mammals, and a plant but no inhibition against beta-glucosidase of almond, alpha-glucosidase of yeast, or chitinase of Bacillus sp. The GlcNAcase inhibitory activity of pochonicine (1) was comparable to nagstatin, a potent GlcNAcase inhibitor of natural origin.
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PMID:Pochonicine, a polyhydroxylated pyrrolizidine alkaloid from fungus Pochonia suchlasporia var. suchlasporia TAMA 87 as a potent beta-N-acetylglucosaminidase inhibitor. 1977 96

The aim of this study was to determine if blood chitotriosidase (Chit) activity and lysosomal enzyme levels might represent markers of disease activity and progression in amyotrophic lateral sclerosis (ALS). It is a survey clinic-based study performed in a tertiary ALS centre. Blood samples were obtained from 76 patients with ALS in different stages of the disease and from 106 healthy individuals serving as controls. Chit activity and the levels of acid alpha-glucosidase, acid alpha-galattosidase A, beta-glucocerebrosidase, and alpha-l-iduronidase were detected using the dried blood spots (DBS) technique. The CHIT1 genotype for exon 10 duplication and for the p.G102S variant was also determined. Chit activity was significantly higher in ALS patients than in healthy individuals. This difference was independent of the genotypes at CHIT1 functional variants. Chit were significantly higher in 34 rapidly progressing patients as compared to 42 with slowly progressive disease. Acid alpha-glucosidase was higher than normal and significantly correlated with the severity of the disease. Glucocerebrosidase and alpha-l-iduronidase activity were significantly lower in patients than in the controls. Alpha-galactosidase A was higher than normal only in rapidly progressing patients. We have employed a very simple and affordable laboratory test to measure blood Chit and lysosomal enzymes activity which could be easily included in the screening of ALS patients recruited in clinical trials. Remarkably, high levels of chitinase and alpha-galactosidase A could help to distinguish patients with fast progression from those with slow progression of the disease and possibly to follow the effects of treatments on neuroinflammation and autophagy.
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PMID:Chitotriosidase and lysosomal enzymes as potential biomarkers of disease progression in amyotrophic lateral sclerosis: a survey clinic-based study. 2556 99


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