Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.7.1.2 (nitrate reductase)
 3,861 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this experiment was the assessment of the influence of various concentrations of H2SeO3 (0.05, 0.5 and 5 mM) on the activity of soil enzymes over 112 days. The lab experiment was performed using soil samples (dust-silt black soil of 1.92% organic C content, pH 7.7), 60% maximal water capacity. The soil samples were treated with a selenic acid water solution at the concentrations mentioned above. As a reference, natural soil was used (without the selenic acid). The activity of the following enzymes was tested: beta-glucosidase, nitrate reductase, urease, dehydrogenase, acid and alkaline phosphatases. The soil was sampled at days 0, 1, 3, 7, 14, 28, 56 and 112. The results of the study have shown that the selenic acid had no effect on the activity of the beta-glucosidase in soil. In the course of the whole experiment, the applied selenic acid inhibited activity of the nitrate reductase up to 70% at 5 mM, and the activity of dehydrogenase was also decreased--by up to 85% at 5 mM, similarly to urease (with the exception of days 14 and 28), and acid phosphatase (until day 56). The activity of alkaline phosphatase was increased by the lowest concentration of selenic acid and decreased by the highest, which was found in the course of the whole experiment. The 5-mM concentration of selenic acid inhibited the activity of all the enzymes tested in this experiment.
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PMID:Influence of various concentrations of selenic acid (IV) on the activity of soil enzymes. 1215 Apr 30

The effect of fructooligosaccharides (FOS) on cecal enzyme activity was studied. Adult male Wistar rats were fed a fiber-free diet supplemented with 5% cellulose, a 5% mixture (1:1) of cellulose and FOS or 5% FOS as a source of fiber for 4 weeks. The cecal content was used to measure azoreductase, beta-glucuronidase, beta-glucosidase, nitrate reductase and nitroreductase activities. Cellulose-fed diet increased significantly body weight gain, food intake and fecal stool weight compared to FOS-fed diet. No differences in food intake between FOS-containing diets were found. FOS-containing diets showed statistically higher weight of cecal content and weight of cecal wall compared with the cellulose group. There were significant differences in cecal enzyme activities between cellulose-fed rats and FOS-fed rats. Cellulose-FOS-fed diet decreased significantly nitroreductase, beta-glucuronidase and beta-glucosidase enzymes, but did not differ statistically in azoreductase and nitrate reductase compared with the control group. FOS-fed diet increased significantly reductive enzymes and decreased hydrolytic enzymes compared with the cellulose group. The incorporation of cellulose in diet seems to affect the prebiotic effect of FOS, since both cellulose and FOS are possible substrates for bifidobacteria proliferation. The results suggest that a mixture of cellulose and FOS as a source of dietary fiber could have a healthier effect on bacterial enzyme activities than each type of dietary fiber alone.
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PMID:Effect of short-chain fructooligosaccharides and cellulose on cecal enzyme activities in rats. 1246 25

The isolation and identification of a novel, slow-growing, scotochromogenic, mycobacterial species is reported. A strain, designated MUP 1182T, was isolated from a cervical lymph node of a 3-year-old child. MUP 1182T is alcohol- and acid-fast, with a lipid pattern that is consistent with those of species that belong to the genus Mycobacterium. It grows slowly at 25-37 degrees C, but does not grow at 42 degrees C. The isolate was revealed to be biochemically distinct from previously described mycobacterial species: it has urease and Tween hydrolysis activities and lacks nitrate reductase, 3-day arylsulfatase and beta-glucosidase activities. Comparative 16S rDNA sequencing showed that isolate MUP 1182T represents a novel, slow-growing species that is related closely to Mycobacterium lentiflavum and Mycobacterium simiae. On the basis of these findings, the name Mycobacterium parmense sp. nov. is proposed, with MUP 1182T (=CIP 107385T=DSM 44553T) as the type strain.
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PMID:Mycobacterium parmense sp. nov. 1528 Feb 80

This study focused on the relationship between plant diversity (six species richness levels) and nutrient retention and enzyme activities associated with carbon, nitrogen and phosphorus cycling in a full-scale constructed wetland (CW) fed with post-treatment domestic wastewater. Effects of plant species richness on nutrient retention and enzyme activities were assessed using soil chemical and zymological methods, respectively. Retention of NH(4)-N and NO(3)-N in the wetland substrate increased with increasing species richness, while phosphorus retention significantly decreased under the richness level of 16 species per plot. Activities of enzymes such as dehydrogenase, beta-glucosidase, invertase, phenol oxidase, L-arsparaginase, protease and nitrate reductase, while they were affected by plant species richness, were strongly depended on the presence or absence of plants in CW substrate, while activities of enzymes such as CM-cellulase, urease and acid phosphatase were strongly depended on plant species richness. We conclude that plant species richness influenced nutrient retention and enzyme activities in the substrate in our subtropical CW; increase plant species richness in CW will likely improve the efficiency of wastewater treatment.
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PMID:Effects of plant diversity on nutrient retention and enzyme activities in a full-scale constructed wetland. 1986 27

Soil microbes are driver of nutrient cycling, with microbial function affected by community composition and soil chemical property. Legume and grass are ubiquitous in many ecosystems, however, their differential effects on microbial function are less understood. Here we constructed compartmented rhizobox planted with stylo (Stylosanthes guianensis, legume) or bahiagrass (Paspalum natatum, grass) to compare their influences on bacterial function and to investigate the determinant of bacterial function. Soils in root compartment and in near (0-5 mm from root compartment) or far (10-15 mm from root compartment) rhizosphere were sampled. Soil chemical properties, bacterial community composition and function were characterized. Results indicate that plant species and distance significantly affected bacterial function. The activities of beta-xylosidase, nitrate reductase and phosphomonoesterase were higher in stylo soil than in bahiagrass soil, while leucine-aminopeptidase activity and nosZ abundance were vice versa. Rhizosphere effect was obvious for the activities of beta-glucosidase, beta-xylosidase, chitinase, and the abundances of AOB-amoA, nirS, nosZ. Statistical analysis revealed that soil chemical property was significantly associated with bacterial function, with a higher coefficient than bacterial community composition. These data suggest that stylo and bahiagrass differentially affect bacterial function, which is affected more strongly by soil chemical property than by community composition.
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PMID:Soil Bacterial Function Associated With Stylo (Legume) and Bahiagrass (Grass) Is Affected More Strongly by Soil Chemical Property Than by Bacterial Community Composition. 3103 40


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