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

In Echinodontium tinctorium the presence of the following enzymes was demonstrated: esterase, maltase, lactase, sucrase, raffinase, diastase, inulase, cellulase, hemicellulase, urease, rennet, and catalase.
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PMID:ENZYME ACTION IN ECHINODONTIUM TINCTORIUM ELLIS AND EVERHART. 1987 34

Circumstantial evidence is presented which indicates that Polyporus volvatus is parasitic. Cultures of Polyporus volvatus and Fomes igniarius may be obtained from the young sporophores by the tissue method. In Polyporus volvatus the presence of the following enzymes was demonstrated: esterase, maltase, lactase, sucrase, raffinase, diastase, inulase, cellulase, hemicellulase, glucosidase, rennet, and catalase. In Fomes igniarius the presence of the following enzymes was demonstrated: esterase, maltase, lactase, sucrase, raffinase, diastase, inulase, cellulase, hemicellulase, glucosidase, urease, rennet, and catalase.
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PMID:STUDIES IN WOOD DECAY : II. ENZYME ACTION IN POLYPORUS VOLVATUS PECK AND FOMES IGNIARIUS (L.) GILLET. 1987 5

Taking a long-term fertilized paddy soil in Taihu Lake region as research object, the enzyme activities in <2, 2-20, 20-200, and 200-2000 microm aggregates under no fertilization (NF), chemical fertilization (CF), chemical fertilization plus straw return (CFS), and chemical fertilization plus pig manure (CFM) were investigated. Fertilization promoted the formation of 200-2000 microm aggregates significantly. The enzyme activities differed with aggregates' particle-size. Urease and invertase activities were the highest in <2 microm aggregates, whereas the activities of cellulase, polyphenoloxidase and FDA hydrolase were the highest in 200-2000 microm aggregates. Fertilization, especially the combined fertilization of inorganic and organic fertilizers, increased the activities of urease, invertase, cellulase and FDA hydrolase in 200-2000 microm aggregates significantly. With the geometric mean (GMea) of the five test enzyme activities as the integrative index of soil enzyme activities, it was found that under fertilization, the GMea was significantly higher in 200-2000 microm aggregates, suggesting the high sensitivity of enzyme activities in larger particle-size aggregates to fertilization practices. Long-term inorganic plus organic fertilization could enhance the soil bio-function via the promotion of the formation of larger particle-size aggregates and the enzyme activities in these aggregates.
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PMID:[Responses of enzyme activities in different particle-size aggregates of paddy soil in Taihu Lake region of China to long-term fertilization]. 2003 Jan 40

We evaluated the use of polyacrylate polymers to aid phytostabilization of mine soils. In a pot experiment, perennial ryegrass was grown in a mine soil and in uncontaminated soil. Growth was stimulated in the polymer-amended mine soil compared with an unamended control, and water-extractable levels of soil Cu and Zn decreased after polymer application. In an experiment performed in six 60-cm-diameter cylinders filled with fertilized mine soil, polymers were applied to three cylinders, with the remainder used as unamended control. Total biomass produced by indigenous plant species sown in polymer-amended soil was 1.8 (Spring-Summer) or 2.4 times (Fall-Winter) greater than that of plants from unamended soil. The application of polymers to the mine soil led to the greatest activity of soil enzymes. Soil pH, biomass of Spergularia purpurea and Chaetopogon fasciculatus, and activities of protease and cellulase had large loadings on principal component (PC)1, whereas growth of Briza maxima and the activities of urease, acid phosphatase, and beta-glucosidase had large loadings on PC2. The treatments corresponding to controls were located on the negative side of PC1 and PC2. Amended treatments were on the positive side of PC2 (Spring-Summer) or on the positive side of PC1 (Fall-Winter), demonstrating differential responses of plants and soil parameters in the two growth cycles.
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PMID:Use of insoluble polyacrylate polymers to aid phytostabilization of mine soils: effects on plant growth and soil characteristics. 2004 4

Changes in extracellular enzyme activities and microbial populations were studied during the normal composting and vermicomposting of fruitpulp, vegetable waste, groundnut husk and cowdung. The microbial numbers and their extracellular enzyme profiles showed relative variation and were found increasingly more abundant in vermicompost than in normal compost leading to the conversion of agricultural waste into value added product. In vermicompost, the maximum enzyme activities (cellulase, amylase, invertase, protease and urease) were observed during 21-35 days. The cellulase, amylase and protease activities of vermicompost reached the maximum values by 28th day of 1175, 825 microg reducing sugar g(-1) hr(-1) and 28 micro mol of aminoacid g(-1) hr(-1) of vermicompost samples respectively. Similarly the invertase and urease activities reached to peak values of 876 microg reducing sugar g(-1) hr(-1) and 197 microg NH4(+)-N g(-1) ha(-1) sample on 35th day respectively. Most of the enzymes showed correlation with change in number and types of different microbial groups like bacteria, fungi and actinomycetes during vermicomposting with maximum number of 126 x 10(6), 28 x 10(4) and 93 x 10(5) CFU g(-1) sample respectively. In contrast delayed greatest enzyme activities were observed on 42-49th day i.e., last days of normal composting. Earthworms stimulated biochemical activity and nutrient cycling by 40-45% contributing to the reduction of period of degradation of agricultural wastes resulting in maturation of vermicompost by 28th day.
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PMID:Comparative assessment in enzyme activities and microbial populations during normal and vermicomposting. 2032 98

From November 2007 to May 2009, a simulation test was conducted in a Pleioblastus amarus plantation in Rainy Area of West China to study the effects of nitrogen deposition on the activities of soil enzymes. Four treatments were installed, i.e., control (0 g N x m(-2) x a(-1)), low nitrogen (5 g N x m(-2) x a(-1)), medium nitrogen (15 g N x m(-2) x a(-1)), and high nitrogen (30 g N x m(-2) x a(-1)). Half year after N deposition, 0-20 cm soil samples were collected monthly, and the activities of peroxidase, polyphenol oxidase, cellulase, sucrase, urease, and acid phosphatase were determined. All test enzyme activities had apparent, seasonal variation, with the peak of cellulase, suerase, and acid phosphatase activities in spring, of urease activity in autumn, and of peroxidase and polyphenol oxidase activities in winter. Nitrogen deposition stimulated the activities of polyphenol oxidase, sucrase, urease, and acid phosphatase, inhibited cellulase activity, but had no significant effects on peroxidase activity. The test P. amurus plantation ecosystem was N-limited, and nitrogen deposition stimulated the decomposition of soil organic matter by microbe-enzyme system.
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PMID:[Soil enzyme activities in a Pleioblastus amurus plantation in Rainy Area of West China under simulated nitrogen deposition]. 2035 60

Surface soil samples were collected from a wastewater-irrigated agricultural area near a smelter in the Xinluo District of Longyan City, Pujian Province, and their basic physical and chemical properties, activities of urease, cellulase, alkaline phosphomonoesterase, polyphenol oxidase and catalase, and contents of Cu, Cd, Pb and Zn were determined, aimed to approach the effects of heavy metals pollution and soil properties on the activities of soil enzymes. Correlation analysis showed that the total and available contents of soil Cu, Cd, Pb and Zn had significant positive correlations with the activities of soil urease, cellulase, alkaline phosphomonoesterase and polyphenol oxidase, but significant negative correlation with the activity of soil catalase. Soil pH had significant positive correlation with the activity of soil alkaline phosphomonoesterase, and soil silt content had significant negative correlation with the activity of soil catalase. Path analysis showed that Cu, Cd, Pb and Zn pollution promoted the activities of soil urease, cellulase and polyphenol oxidase, but had less effects on the activity of soil alkaline phosphomonoesterase. Soil available Cu, Cd, Pb and Zn didn't directly affect the activity of soil catalase, but indirectly inhibited it significantly. Soil physical and chemical properties had greater effects on soil enzyme activities, e.g., alkaline-hydrolyzable N directly inhibited the activity of soil urease, total P directly stimulated the activities of soil alkaline phosphomonoesterase and catalase and indirectly stimulated the activity of soil cellulase via available P, available P directly promoted the activity of soil cellulase but inhibited the activities of soil alkaline phosphomonoesterase and catalase, total K directly inhibited the activities of soil alkaline phosphomonoesterase and polyphenol oxidase, available K stimulated the activity of soil catalase via available P, and particle composition had significant effects on the activities of soil polyphenol oxidase and catalase. The above results demonstrated that because of the complicated and uncertain relationships between the contents of soil Cd, Pb, Zn and Cu and the activities of the five soil enzymes, it should be cautious to use the test enzyme activities to indicate soil heavy metals pollution.
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PMID:[Changes of soil enzyme activities in heavy metals polluted region: a case study in a wastewater-irrigated agricultural area near a smelter in Xinluo District of Longyan City, Fujian Province]. 2035 74

With the continuing increase in human activities, ecologists are increasingly interested in understanding the effects of acid rain on litter decomposition. Two dominant litters were chosen from Zijin Mountain in China: Quercus acutissima from a broad-leaved forest and Pinus massoniana from a coniferous forest. The litters were incubated in microcosms and treated with simulated acid rain (gradient pH levels). During a six-month incubation, changes in chemical composition (i.e., lignin, total carbohydrate, and nitrogen), litter mass losses, soil pH values, and activities of degradative enzymes were determined. Results showed that litter mass losses were depressed after exposure to acid rain and the effects of acid rain on the litter decomposition rates of needles were higher than on those of leaves. Results also revealed that simulated acid rain restrained the activities of cellulase, invertase, nitrate reductase, acid phosphatase, alkaline phosphatase, polyphenol oxidase, and urease, while it enhanced the activities of catalase in most cases during the six-month decomposition process. Catalase and polyphenol oxidase were primarily responsible for litter decomposition in the broad-leaved forest, while invertase, nitrate reductase, and urease were primarily responsible for litter decomposition in the coniferous forest. The results suggest acid rain-restrained litter decomposition may be due to the depressed enzymatic activities. According to the results of this study, soil carbon in subtropical forests would accumulate as a long-term consequence of continued acid rain. This may presumably alter the balance of ecosystem carbon flux, nutrient cycling, and humus formation, which may, in turn, have multiple effects on forest ecosystems.
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PMID:Effect of simulated acid rain on the litter decomposition of Quercus acutissima and Pinus massoniana in forest soil microcosms and the relationship with soil enzyme activities. 2038 10

European frameworks for the ecological risk assessment (ERA) of contaminated sites integrate information from three lines of evidence: chemical, ecotoxicological, and ecological. Regarding the last one, field observations at the contaminated sites are compared to reference site(s) and the differences recorded are analysed at the light of a cause-effect relationship, taking into account the site-specific contamination. Thus, included in the tier 2 of a site-specific risk assessment that is being carried out in an deactivated uranium mining area, a battery of soil enzyme activities (dehydrogenases, urease, arysulphatase, cellulase, acid phosphate) and potential nitrification were assessed in seven sampling sites (A-D-E-F-G-H-I) at different distances from the mine pit. These parameters have been considered good indicators of impacts on soil microbial communities and, subsequently, on soil functions. Soil enzyme activities were impaired in the most contaminated site (A, near the mine pit), for which a higher degree of risk was determined in the tier 1 of ERA. Three other sites within the mining area (F, G, and D) were discriminated on the basis of their low microbial activity, using uni- and multivariate approaches, and validating what had been previously found with chemical and ecotoxicological lines of evidence. We observed considerable among-site heterogeneity in terms of soil physical and chemical properties, combined with seasonal differences in enzyme activities. Still, the correlation between microbial parameters and soil general physical and chemical parameters was weak. In opposition, significant and negative correlations were found between soil enzyme activities and several metallic elements (Al, Be, Cu, U). These findings suggest a clear correlation between compromised soil function (nutrient recycling) and metal contamination. Such information reinforces the evidence of risks for some sites within the mining area and is an important contribution for the usefulness of soil enzyme activities for evaluating changes in soil health.
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PMID:Impaired microbial activity caused by metal pollution: A field study in a deactivated uranium mining area. 2201 59

Based on the measurements of soil nutrient contents and enzyme activities and the canonical correspondence analysis (CCA), this paper studied the relationships between soil nutrient contents and soil enzyme activities in different age Pinus massoniana stands in Three Gorges Reservoir Area. Among the test stands, mature stand had the highest contents of organic matter, total nitrogen, ammonium nitrogen, and available phosphorus in 0-20 cm soil layer, followed by middle-aged stand, and nearly-mature stand. With the increase of the stand age, soil invertase activity increased after an initial decrease, cellulase and polyphenoloxidase activities decreased gradually, while urease and peroxidase activities decreased after an initial increase. CCA analysis showed that the effects of the main soil parameters on the soil enzyme activities in the stands ranked in the sequence of total nitrogen > organic matter > pH > bulk density > ammonium nitrogen > available phosphorus. Soil invertase activity had significant positive correlations with soil organic matter, total nitrogen, and total phosphorus, while soil peroxidase activity significantly negatively correlated with soil organic matter, total nitrogen, total phosphorus, and bulk density. The soil was rich in main nutrients, invertase activity was relatively high, while peroxidase activity was relatively low. The activities of soil invertase, cellulase and peroxidase could be used as the good biological indicators in evaluating soil quality and fertility.
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PMID:[Relationships between soil nutrient contents and soil enzyme activities in Pinus massoniana stands with different ages in Three Gorges Reservoir Area]. 2258 71


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