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

The hydroxylsine-linked disaccharide unit, 2-O-alpha-D-glucopyranosyl-O-beta-D-galactopyranosyl-hydroxylysine (Glc-Gal-Hyl), prepared from collagens, was hydrolyzed by a glucohydrolase present in rat spleens and lungs. This disaccharide unit was scarcely hydrolyzed by homogenates of intestines, livers, and kidneys, which had a high alpha-D-glucosidase activity for neutral glucosides. The Glc-Gal-Hyl glucohydrolase was purified from rat spleens by affinity chromatography and gel filtration to the extent that sodium dodecyl sulfate/polyacrylamide gel electrophoresis gave a single band stained by Coomassie blue G-250. This purified glucohydrolase had a pH optimum around 5.8, and the Michaelis constant was 5.9 mM when Glc-Gal-Hyl was used as a substrate. This enzyme did not hydrolyze neutral glucosides. It is concluded that this Glc-Gal-Hyl glucohydrolase is responsible for catabolism of the hydroxylsine-linked disaccharide unit derived from collagens in mammals.
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PMID:Enzymatic hydrolysis of disaccharide unit of collagen. Isolation of 2-O-alpha-D-glucopyranosyl-O-beta-D-galactopyranosyl-hydroxylysine glucohydrolase from rat spleens. 746 Sep 18

A new substrate, 4-O-beta-D-galactopyranosylmaltotetraose (Gal-G4) is applied for the determination of alpha-amylase in serum and urine in a coupled assay with alpha-glucosidase (EC 3.2.1.20), glucokinase (EC 2.7.1.2) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) as auxiliary enzymes. Gal-G4 having a 4-position of the non-reducing-end glucose residue modified by a beta-galactopyranose group is resistant for degradation by alpha-glucosidase as auxiliary enzyme. Moreover, this substrate is hydrolyzed at just one position by alpha-amylase in serum and urine. More than 99% of the products generated from Gal-G4 by alpha-amylase are identified 4-O-beta-D-galactopyranosylmaltose (Gal-G2), maltose, respectively. Glucose and maltose do not interfere the value of alpha-amylase activity at least up to 0.056 mmol/l (1 g/dl) glucose and 0.027 mmol/l (1 g/dl) maltose, respectively. We are now carrying out this work under the authority of The Enzyme committee of Japanese Society of Clinical Chemistry (JSCC) as a standard method for determination of alpha-amylase in clinical chemistry.
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PMID:Determination of alpha-amylase using 4-O-beta-D-galactopyranosylmaltotetraose (Gal-G4) as a substrate. 962 Apr 65

The study of gene regulation in many organisms has been facilitated by the development of reporter genes. The authors report the use of lacZ from Streptococcus thermophilus, a gene encoding a beta-galactosidase, as a reporter for the fungal pathogen Candida albicans. As test cases, Strep. thermophilus lacZ was placed under control of three different C. albicans promoters: MAL2 (maltase), inducible by maltose; HWP1 (hyphal cell wall protein), induced by conditions that promote filamentous growth; and ACT1 (actin). These constructs were each integrated into the C. albicans genome and beta-galactosidase activity was readily detected from these strains, but only under the appropriate growth conditions. Beta-galactosidase activity could be detected by several methods: quantitative liquid assays using permeabilized cells, colorimetric assays of colonies replicated to paper filters, and in situ coloration of colonies growing on medium containing the indicator X-Gal. These results show the usefulness of STREP: thermophilus lacZ as a monitor of gene regulation in this medically important yeast.
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PMID:Development of Streptococcus thermophilus lacZ as a reporter gene for Candida albicans. 1132 Jan 22