Search results for "Microbio"
showing 10 items of 8741 documents
Carbon decomposition of the topsoils and soil fractions under forest and pasture in the western Brazilian Amazon basin, Rondonia
2000
The topsoils of two sites, comprising natural forest and 4- and 20-year-old pastures, respectively, were selected in Rondonia to evaluate the changes of soil organic matter due to pasture establishment. These changes were evaluated by measuring the proportions of the C and N associated with clay and silt fractions, and by the C decomposition (CD) rate of the whole topsoils and their size fractions. The topsoils studied had large proportions of C and N associated with fine fractions, especially with clay fractions. The CD rate of the silt fractions was higher than that of the clay fractions under the two forest topsoils and under the 20-year-old pasture. The CD rate of the silt fractions und…
Evidence for the involvement of acylglycerides on chitin synthetase activity inCandida albicans
1991
The effect of a lipase activity (EC 3.1.1.3) on the chitin synthetase from Candida albicans has been studied, both on the active and the trypsin activated enzyme. Removal of fatty acids from acylglycerides by lipase has an inhibitory effect on the activity as well as on the ‘in vitro’ activation process by trypsin in the membrane-bound enzyme and in the chitosomes. This would indicate that an adequate lipid environment is required for both the activation process and proper function of the synthetase activity.
2-Oxoglutarate decarboxylase ofLeuconostoc oenos
1990
InLeuconostoc oenos, the typical organism of the malolactic fermentation of wine, a 2-oxoglutarate decarboxylase was detected. This inducible enzyme decarboxylates 2-oxoglutarate but not pyruvate. The resulting succinaldehydate is rapidly reduced to 4-hydroxybutyrate or oxidized to succinate in further reactions. 2-Oxoglutarate decarboxylase is thiamin-diphosphate-dependent; the pH optimum is at 5.3 and theK m value for 2-oxoglutarate is 1.8 mmol/L.
Synthesis of the neurotoxin quinolinic acid in apoptotic tissue from Suberites domuncula: cell biological, molecular biological and chemical analyses
2002
Sessile marine animals, such as sponges, are prone to infection by prokaryotic as well as by eukaryotic attacking organisms. In the present study we document for the first time that in tissue from sponges which underwent apoptosis, a toxic compound is produced which very likely controls the elimination of the dying tissue. The marine sponge Suberites domuncula develops in the field occasionally apoptotic tissue areas which are rapidly eliminated. In the present study apoptosis was induced in S. domuncula by exposing the specimens in aquaria to 5 µg/ml Dip or by maintaining the sponges for 3 - 5 days under non-aeration conditions. After that treatment only one eukaryotic epibiont, the mollus…
Polysaccharide‐containing Cell‐wall Polymers of Archaea
2002
Introduction Historical Outline Chemical Structure Glutaminylglycan Heteropolysaccharide Methanochondroitin Pseudomurein S-Layer Lipoglycan Occurrence Functions Biochemistry Biosynthesis Biological Activity Molecular Genetics Biodegradation Methanochondroitin Pseudomurein Production (Producers, World market, Applications, Patents) Outlook and Perspectives Acknowledgements Keywords: glutaminylglycan; heteropolysaccharide; methanochondroitin; pseudomurein; S-layer (glyco-)protein; Archaea; cell envelope; cell-wall polysaccharides
A49 LACTOBACILLI DEGRADE WHEAT AMYLASE TRYPSIN INHIBITORS (ATI) TO AMELIORATE GUT DYSFUNCTION INDUCED BY IMMUNOGENIC WHEAT PROTEINS
2019
BACKGROUND: Wheat-related disorders involve a wide spectrum of conditions, triggered by the ingestion of gluten-containing cereals. The induction of gluten-specific immune responses in celiac disease is well established. However, the contribution of gluten and/or non-gluten proteins in the generation of symptoms in other wheat-related disorders is controversial. Amylase trypsin inhibitors (ATIs) are pest-resistant molecules in modern wheat with TLR4-activating capacities. AIMS: We investigated the role of ATIs in the generation of gut barrier dysfunction and dysmotility in wild-type mice as well as in the severity of gluten-induced immunopathology in genetically predisposed mice. We also de…
Mannosyl transferases inSaccharomyces cerevisiae: Evidence for the occurrence of ectomannosyltransferase activity
1981
The subcellular distribution of mannosyltransferases inSaccharomyces cerevisiae was studied following the separation of the plasma membrane from other intracellular membranous systems. Most of the activity was linked to internal membranes, and the rest was located at the level of the plasma membrane. Yeast plasma membranes coated on their external face with concanavalin A when incubated with GDP-[U-14C]mannose incorporated 20% less [U-14C]mannose in glycoproteins and 110% more in glycolipids than plasma membranes alone. This suggested that part of the total mannosyltransferase activity of the plasma membrane is located on its outer surface. A significant incorporation of radioactive mannose…
Addition of reducing agent dithiothreitol improves 4-decanolide synthesis by the genus Sporidiobolus.
2000
Two species of the genus Sporidiobolus, S. johnsonii and S. ruinenii, were used to study the effect of the reducing agent, dithiothreitol (DTT), on 4-decanolide production using ricinoleic acid as the substrate. The results indicate that the addition of DTT into the cultures significantly enhanced 4-decanolide biosynthesis by the two species.
Isolation and identification of roseotoxin S from cultures of the fungus Trichothecium roseum
1988
The structure of reseotoxin S, a new cyclodepsipeptide of the fungus Trichothecium roseum, is described. It consists of three amino acids and two hydroxy acids. Besides the structure, possibilities of proof and isolation as well as analytical data are given.
Microfungal community structure in anthropogenic birch stands in central Finland
2002
We describe the soil microfungal communities in 30-year-old birch (Betula pendula Roth) stands planted either on former spruce forest soil (BS) or on former arable soil (BF) and compare these with the soil microfungal communities in spruce forests (S), arable fields (F) and old deciduous forests (D). Fungi were isolated from 0- to 3-cm and 3- to 6-cm samples collected in September 1997 and May 1998. Principal components analysis differentiated fungal communities in the S and BS sites from those in the other site types. The Morisita-Horn index of similarity indicated that fungal communities in the F and BF sites were less similar to those in the other site types. Fungal communities of the BS…