Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.25.1 (deoxyribonuclease)
 1,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An extract made from the supernatant of Neisseria gonorrhoeae Gc2 strain 1291 degraded the Gc2 polysaccharide antigen. Chemical analysis of this polysaccharide indicated it contains glucose, galactose, glucosamine, galactosamine, glucosamine-6-phosphate, heptose, 2-keto-3-deoxyotonate, and ethanolamine and is the polysaccharide component of gonococcal lipopolysaccharide. Degradation of the polysaccharide by sonic extracts resulted either in complete loss of antigenicity and immunogenicity or in partial degradation to subunits that could inhibit the Gc2-specific hemagglutination inhibition. The factors responsible for degradation were destroyed by heating at 100 degrees C for 5 min or by Pronase digestion, but were unaffected by ribonuclease, deoxyribonuclease, Mg2+, Ca2+, or ethylenediaminetetraacetic acid. The process was pH dependent, with optimal activity occurring at pH 7. Sonic extract supernatants from group B and C meningococcal strains contained degrading properties, whereas similar extracts produced from Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Streptococcus pneumoniae type II failed to degrade the Gc2 polysaccharide.
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PMID:Degradation of the polysaccharide component of gonococcal lipopolysaccharide by gonococcal and meningococcal sonic extracts. 7 94

Cell walls were isolated by mechanical disruption of mid-log phase cells of Bacillus stearothermophilus NCA 1503-4R grown in Trypticase-yeast extract-fructose medium at 55 C. The cell walls were purified by treatment with sodium dodecyl sulfate (SDS) and incubation with deoxyribonuclease and trypsin. The cell wall peptidoglycan contained glucosamine, muramic acid, alpha, epsilon-diaminopimelic acid, and glutamic acid. Low amounts of glycine, galactosamine, serine, aspartic acid, lysine, and valine were also present. The relative mole ratios of glutamic acid-alpha, epsilon-diaminopimelic acid-glycine-alanine were 1.00:1.26:0.08:1.55. The cell walls were free from ribonucleic acid and deoxyribonucleic acid and contained less than 0.2% chloroform-methanol extractable lipid and 0.09 mumole of phosphorus per mg of cell wall. Teichoic acid was not detected in the cell walls of this organism. Cell walls isolated without treatment with SDS contained 7.5% chloroform-methanol extractable lipid, 0.24 mumole of phosphorus per mg of cell wall, and relatively high concentrations of all amino acids. These results suggest that the extracted lipid is not a cell wall component per se, but a contaminant from the lipoprotein cell membrane.
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PMID:Chemical composition of the cell walls of Bacillus stearothermophilus. 603 16

Colonic mucins may serve as a defense mechanism by binding bacterial, viral, or dietary lectins, thereby preventing them from attaching to the intestinal epithelium. Presumably, the composition of the mucins would be responsible for this phenomenon, and the composition of mucins from mature mammals would be the most effective in binding lectins. To determine whether differences in diet and/or age affect the composition of colonic mucins, we scraped fresh colonic mucosae from pigs at 0 (n = 3), 7 (n = 3), 21 (n = 3), and 180 (n = 3) d of age and purified the mucins from these mucosal scrapings. Mucins were purified by ribonuclease and deoxyribonuclease digestion, high-performance size-exclusion chromatography, and cesium chloride density-gradient ultracentrifugation. The 180-d-old pig was considered mature. No changes were observed in any of the variables analyzed in the 7-d-old animals. No changes were observed in quantities of galactosamine and galactose. The amounts of fucose and glucosamine increased by 165 and 37%, respectively, (p < 0.05) from d 0 to d 21 in the sow-fed animals, at which time fucose and glucosamine content were 48 and 22% greater, respectively, than in the 21-d-old, artificially fed group (p < 0.05). A further significant increase in fucose content was observed in the mucins from mature animals. The sulfate content in the 21-d-old, sow-fed animals was significantly lower than in both the newborn and the 21-d-old artificially fed animals. The sulfate content in all three of these groups, however, was significantly higher than that observed in the mucins of mature animals.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Age and diet affect the composition of porcine colonic mucins. 837 12