Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.3.4.6 (urease)
 7,490 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A simplified, concise scheme was developed for the identification of nonfermentative, gram-negative bacteria which have most frequently been reported in the literature as definite or possible agents of human disease. These organisms included apyocyanogenic Pseudomonas aeruginosa, P. fluorescens, P. putida, P. stutzeri, P. maltophilia, P. putrefaciens, P. cepacia, P. alcaligenes, FLAVOBACTERIUM SPECIES, Bordetella bronchiseptica, Acinetobacter anitratum (Herellea vaginicola), A. Iwoffi (Mima polymorpha), Moraxella species, Alcaligenes odorans and Alcaligenes species. The tests used for identification included production of cytochrome oxidase, amylase, deoxyribonuclease, gelatinase, urease and Beta-galactosidase; motility; oxidation of one per cent glucose and ten per cent lactose; fluorescence; indole, hydrogen sulfide and nitrogen gas production; denitrification of nitrites; growth at 42C; penicillin sensitivity and production of an aromatic odor and greenish discoloration on blood agar. Using this scheme, 85 per cent of 243 isolates (unknowns and reference strains) were identified to genus and species. Of the 15 per cent remaining, 11 per cent were identified as alkaline organisms and four per cent were unidentifiable.
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PMID:Identification of nonfermentative gram-negative bacteria in the clinical laboratory. 16 60

Using the general concept of a dry multilayer analytical element, we can change chemical procedures and configurations to assay several blood components. In the assay of serum urea nitrogen, urease in the reagent layer catalyzes the hydrolysis of urea. A semipermeable membrane excludes aqueous base, but allows ammonia to diffuse to an underlying indicator layer. For the amylase determination, the enzyme hydrolyzes a dyed-starch substrate coated on top of the spreading layer; this produces small fragments, which diffuse to a registration layer. The increase of absorbance at 540 nm is correlated with amylase activity. Bilirubin complexes with a cationic polymer at the interface between the spreading and reagent layers. The direct reading at 460 nm allows determination of total bilirubin in the range 1 to 500 mg/liter. Tirglycerides are hydrolyzed in the spreading layer, and the resulting soluble glycerol readily diffuses into the reagent layer, where it is phosphorylated and subsequently oxidized by glycerophosphate oxidase to yield dihydroxyacetone phosphate and hydrogen peroxide. Peroxidase catalyzes production of a color commensurate with the hydrogen peroxide produced.
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PMID:Multilayer film elements for clinical analysis: applications to representative chemical determinations. 56 6

The enzymes used in the identification of Gram negative bacteria belonging to the families of Enterobacteriaceae, Vibrionaceae, Parvobacteriaceae, Pseudomonadaceae and to the genera Alteromonas, Xanthomonas, Alkaligenes, Flavobacterium are classified arbitrarily by the author into enzymes essential for the diagnosis of the family (oxidase, nitratase), enzymes useful in the diagnosis of the genus or the species (ONPG-hydrolase, urease, oxidative desaminase, lysine decarboxylase and ornithine, arginine dihydrolase, thiosulphate reductase, pectinase), and into enzymes sought to confirm the diagnosis (tetrathionate reductase, gelatinase, lipase, DNase, amylase, beta-xylosidase, lecithinase). The technics permitting their identification are described and their distribution in the species and genera studied is reported.
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PMID:[Research technics of enzymes used in the diagnosis of gram negative bacteria (author's transl)]. 74 48

During a survey conducted in Colombia a new isolate of Bacillus thuringiensis that showed toxicity toward Culex quinquefasciatus, Cx. pipiens, Aedes aegypti, and Anopheles stephensi larvae was isolated. Parasporal crystals were spherical in shape and showed a great degree of similarity with those produced by the reference strain of Bacillus thuringiensis subsp. israelensis. Supernatant fraction of the whole culture was not toxic, and heat-stable exotoxin production was negative. Catalase, urease, arginine dihydrolase, amylase, lecithinase, acetyl-methyl-carbinol, and gelatinase production were positive. Hemolysis on sheep blood agar was alpha-type. The isolate 163-131 showed natural resistance to azolocillin and was sensible to cephoperazone, cephalotin, nalidixic acid, and trimetoprin sulfametoxazole. Flagellar agglutination showed a specific H 30 antigen which allows individualization of this strain as a new serotype and the subspecies name of medellin is proposed.
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PMID:A new serotype of Bacillus thuringiensis from Colombia toxic to mosquito larvae. 134 10

Microbioassays using bacteria or enzymes are increasingly applied to measure chemical toxicity in the environment. Attractive features of these assays may include low cost, rapid response to toxicants, high sample throughput, modest laboratory equipment and space requirements, low sample volume, portability, and reproducible responses. Enzymatic tests rely on measurement of either enzyme activity or enzyme biosynthesis. Dehydrogenases are the enzymes most used in toxicity testing. Assay of dehydrogenase activity is conveniently carried out using oxidoreduction dyes such as tetrazolium salts. Other enzyme activity tests utilize ATPases, esterases, phosphatases, urease, luciferase, beta-galactosidase, protease, amylase, or beta-glucosidase. Recently, the inhibition of enzyme (beta-galactosidase, tryptophanase, alpha-glucosidase) biosynthesis has been explored as a basis for toxicity testing. Enzyme biosynthesis was found to be generally more sensitive to organic chemicals than enzyme activity. Bacterial toxicity tests are based on bioluminescence, motility, growth, viability, ATP, oxygen uptake, nitrification, or heat production. An important aspect of bacterial tests is the permeability of cells to environmental toxicants, particularly organic chemicals of hydrophobic nature. Physical, chemical, and genetic alterations of the outer membrane of E. coli have been found to affect test sensitivity to organic toxicants. Several microbioassays are now commercially available. The names of the assays and their basis are: Microtox (bioluminescence), Polytox (respiration), ECHA Biocide Monitor (dehydrogenase activity), Toxi-Chromotest (enzyme biosynthesis), and MetPAD (enzyme activity). An important feature common to these tests is the provision of standardized cultures of bacteria in freeze-dried form. Two of the more recent applications of microbioassays are in sediment toxicity testing and toxicity reduction evaluation. Sediment pore water may be assayed directly or solvents may be used to extract the toxicants. Some of the solvents used for extraction of organic chemicals are themselves toxic to bacteria (e.g., dichloromethane), requiring exchange with a less toxic solvent (e.g., ethanol, methanol, DMSO). A modification of the Microtox test allows direct assay of solid-phase samples such as sediments. The toxicity reduction evaluation (TRE) must be carried out at wastewater treatment plants whose effluents fail toxicity standards. The TREs require numerous and repeated toxicity assays, thus favoring application of microbioassays. Presently, no single microbioassay can detect all categories of environmental toxicants with equal sensitivity. Therefore, a battery of tests approach is recommended. The differential sensitivity of alternative tests may, in fact, be exploited. Further research is needed to construct strains of genetically engineered microorganisms or isolate microorganisms or enzymes that respond to specific classes of toxicants. These can be combined into batteries appropriate for different environments or test objectives.
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PMID:Bacterial and enzymatic bioassays for toxicity testing in the environment. 150 75

Thirty strains were isolated from pasteurized soil samples by enrichment culture in aerobiosis at 32 degrees C in a minimal medium containing one of the following compounds as sole source of carbon and energy: quinate, p-hydroxybenzoate, phthalate, isophthalate or trimellitate. These bacteria were rods (0.8 X 2-7 micron), motile by peritrichous flagella. Endospores were oval (1.4-1.8 X 2 micron) and distinctly swelled the sporangia. The Gram reaction was variable but the Gram type was positive. Colonies were smaller on peptone (0.4%) agar than on minimal salts-glucose (0.2%) agar. The following characters were always present: growth in the presence of lysozyme, cytochrome c oxidase, catalase, nitrate assimilation, urease, amylase and L-glutamate dehydrogenase. The cells contained glycogen. In anaerobiosis, glucose was not fermented and nitrate was not used as a respiratory acceptor of electrons. Of 215 substrates tested, 31 (including 9 aromatic compounds) were used as sole carbon and energy sources by all 30 strains, and 38 substrates (including 13 aromatic compounds) were used by only some of them; 146 substrates (including 49 aromatic compounds) were not used by any of the 30 strains. No amino acid could be used as sole carbon and energy source. Numerical analysis of the 30 strains showed an aggregate cluster made of 5 phena. The mean G + C content of the DNA was 55 +/- 0.6 mol %. The described bacteria are clearly different from the 2 known species of the second morphological group which cannot ferment carbohydrates: Bacillus brevis and B. azotoformans. Strain Q1 (ATCC 29948) is the holotype of Bacillus gordonae sp. nov.
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PMID:[Bacillus gordonae sp. nov., a new species belonging to the second morphological group, degrading various aromatic compounds]. 367 81

Twenty-one strains of pink-pigmented bacteria, isolated from human clinical specimens and an environmental source, were compared with Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. These isolates were gram-negative, oxidative rods which were motile by means of a single polar flagellum; gave positive catalase, indophenol oxidase, urease, and amylase reactions; and grew slowly at 30 degrees C. Fourteen isolates conformed to the designated type strains Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. The remaining seven strains represented an undescribed taxon. These pink bacteria appear to be invaders of debilitated patients with an underlying chronic disease.
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PMID:Pseudomonas mesophilica and an unnamed taxon, clinical isolates of pink-pigmented oxidative bacteria. 649 Aug 48

Activities of twelve hydrolytic enzymes in the digestive tract of young rabbits before weaning (4 weeks old) and adult rabbits (3 months old) were measured. The principal digestive enzymes in both groups of rabbits appeared to be amylase (EC 3.2.1.1), maltase (EC 3.2.1.20), pectinase (EC 3.2.1.15) and proteinases. The stomach of young rabbits contained most of the lipolytic activity and 45.7% of the total proteolytic activity of the digestive tract. The highest specific activities (per g digesta) of amylase, maltase and proteinase in young rabbits were found in the small intestine. Total activities (per segment) of amylase and maltase in the small intestine and the caecum were similar. Activities of cellulase (EC 3.2.1.4), inulinase (EC 3.2.1.7) and beta-glucosidase (EC 3.2.1.21) were low and activity of pectinase was fairly high in all segments of the digestive tract. The highest activity of urease (EC 3.5.1.5) was found in the caecum. Enzymic profiles of the colonic chymus resembled those of the caecum. Total hydrolytic activity was lower in the colon than in the caecum. Specific activities of amylase and invertase (EC 3.2.1.26) were lower and those of inulinase and lactase (EC 3.2.1.23) higher in 4-week-old rabbits than in 3-month-old rabbits. Gastric proteinase represented almost half of the total proteolytic activity of the digestive tract, whereas lipolytic activity of gastric contents was not found in measurable quantities in adult rabbits. The caecal contents of adult rabbits contained most of the total activity of lipase (EC 3.1.1.3), cellulase, xylanase (EC 3.2.1.32), pectinase, lactase, invertase, beta-glucosidase and urease present in the digestive tract.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Distribution of activity of hydrolytic enzymes in the digestive tract of rabbits. 753 89

Tests were conducted to determine the effects of fungicides, captafol and chlorothalonil, on microbial and enzymatic activities in sandy loam. The results indicated that when captafol or chlorothalonil was added to the sandy loam, bacterial and fungicidal populations initially decreased with the treatments but recovered rapidly to levels similar to those in the controls. No inhibition on oxidation of soil ammonia or organic sulfur was observed. The fungicide treatments significantly increased oxygen consumption from the decomposition of organic matter indigenous to the soil. Both fungicides suppressed invertase and amylase for 1 day. However, the inhibitory effect disappeared after 2 days. Captafol depressed dehydrogenase for 4 days and recovered to equal to that of control after 7 days. No inhibitory effect on urease and phosphatase was shown with the fungicidal treatments. Although some stimulatory influences of fungicides on microbial and enzymatic activities were found in the soil, in no instance were the effects dramatic or sufficient enough to be considered important to soil fertility.
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PMID:Effect of fungicides, captafol and chlorothalonil, on microbial and enzymatic activities in mineral soil. 842 61

Observations were carried out of actual acidity, volatile fatty acid (VFA) concentrations, enzyme activity in the rumen, total protein, urea, total lipid and glucose in the serum of conventional (CL) and gnotobiotic lambs (GL) in the period of milk nutrition. The inoculum of gnotobiotic lambs contained Streptococcus bovis, Prevoxella ruminicola, Butyrivibrio fibrisolvens and Selenomonas ruminantium at a concentration of 1.10(6) each. Throughout the observation period the pH of the rumen contents of gnotobiotic lambs ranged within 6.5-6.8 with a significant difference at an age of 7 weeks. Total VFA concentrations in the rumen contents were increased in the CL throughout milk nutrition: the differences at 4 and 5 weeks of age were significant. Total VFA in the conventional lambs revealed an increasing tendency between weeks 4 and 7, reaching higher levels at 7 weeks of age (57.1 mmol.l-1), whereas in the gnotobiotic animals the range (24.3-30.1 mmol.l-1) was narrow and the peak occurred at 6 weeks of age. In GL significantly increased molar proportions of acetic acid were observed whereas in CL the molar proportions of propionic acid proved to be significant increased. The molar proportions of butyric and valeric acids were increased in CL but the group differences were not significant. In GL no isoacids were found. Alpha amylase (E.C.3.2.1.1.) activity of the rumen contents was significantly increased in GL between weeks 2 and 6 of age whereas cellulase (endoglucanase E.C.3.2.1.4. and cellobiohydrolase E.C.3.2.1.91.) activity was significantly increased in 4-week-old CL. Over the whole period of milk nutrition no significant differences were observed in urease (E.C.3.5.1.5.) activity of the rumen contents in the examined groups. At 5 weeks of age significantly increased total protein levels were observed in the conventional animals with maximum levels occurring at 4 weeks of age (CL-59.5 g.l-1 GL-55.3 g.l-1). Urea levels in 6-week old conventional lambs were significantly higher than in the gnotobiotic animals (CL-6.4 mmol.l-1 vs. GL-1.9 mmol.l-1). As to glycaemia no significant group differences were recorded. In the conventional animals total lipid levels were significantly increased at 1 and 6 weeks of age with a peak occurring in the first week of life (7.5 g.l-1) whereas in the gnotobiotic lambs a significant increase was observed at 3 weeks of age, the peak being recorded in 4 week-old animals (4.3 g.l-1). Throughout the period of interest the mean daily weight gains in the conventional and gnotobiotic lambs presented 0.164 and 0.162 kg, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Rumen fermentation and metabolic profile in conventional and gnotobiotic lambs. 858 97


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