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51.
Rice straw is valuable resource that has been used as substrate for cost effective production of xylanase under solid-state fermentation by a newly isolated white rot fungi, S. commune ARC-11. Out of eleven carbon sources tested, rice straw was found most effective for the induction of xylanase that produced 4288.3?IU/gds of xylanase by S. commune ARC-11. Maximum xylanase production (6721.9?IU/gds) was observed on 8th day of incubation at temperature (30?°C), initial pH (7.0) and initial moisture content (70.0%). The supplementation of ammonium sulphate (0.08% N, as available nitrogen) enhanced the xylanase production up to 8591.4?IU/gds. The xylanase production by S. commune ARC-11 was further improved by the addition of 0.10%, (w/v) of Tween-20 as surfactant. The maximum xylanase activities were found at pH 5.0 and temperature 55?°C with a longer stability (180?min) at temperature 45, 50 and 55?°C. This xylanase preparation was also evaluated for the pre-bleaching of ethanol-soda pulp from Eulaliopsis binata. An enzyme dosage of 10?IU/g of xylanase resulted maximum decrease in kappa number (14.51%) with a maximum improvement 2.9% in ISO brightness compared to control.  相似文献   
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In general, the members of Lip gene family of Mycobacterium tuberculosis evoke strong immune response in the host. Keeping this fact into consideration, we investigated role of Rv3203, a cell wall associated protein with lipolytic activity, in imparting protection against experimental murine tuberculosis. The data of the present study suggested that archaeosome encapsulated Rv3203 induce strong lymphocyte proliferation, up-regulated Th-1 biased cytokines profile, increased expression of co-stimulatory markers on both antigen presenting cells and T lymphocytes. The immuno-prophylactic response was further modulated by exposure of the animals to zymosan, a TLR2/6 agonist, prior to immunization with archaeosome encapsulated Rv3203. Interestingly, pre-treatment of experimental animals with zymosan boosted strong immunological memory as compared to archaeosome encapsulated Rv3203 as well as BCG vaccine. We conclude that priming of immunized animal with TLR agonist followed by immunization with archaeosomes encapsulated Rv3203 offer substantial protection against tuberculosis infection and could be a potential subunit vaccine based prophylactic strategy.  相似文献   
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The cell type specificity of glycoconjugate synthesis between the epithelial and stromal cells of the uterus is described. Lactosaminoglycans (LAGs) constituted a major fraction of the cell-associated glycoconjugates synthesized by epithelial, but not stromal, cells. Furthermore, LAGs comprised the bulk (greater than 90%) of glycoconjugates that could be released from epithelial cell surfaces by proteases. Several lines of evidence indicate that the epithelial cell-specific lactosaminoglycans appear to interact directly with a cell surface galactosyltransferase (GalTase). This includes the observation that agents that perturb galactosyltransferase function also interrupt epithelial cell adhesion and cause LAG release from the cell layer. In addition, LAGs are galactosylated when UDP-[3H]galactose is added to intact epithelial cell layers. Interference with cell surface GalTase activity with alpha-lactalbumin or UDP-galactose, but not other agents, specifically interrupted epithelial cell adhesion; however, the same agents had absolutely no effect on stromal cells. Collectively, these studies describe the novel occurrence of lactosaminoglycans on cell surfaces in an adult tissue other than hematopoietic cells and provide evidence for cell type-specific involvement of lactosaminoglycans in uterine cell adhesion processes.  相似文献   
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The synthesis of phosphatidylserine in two gram-positive aerobic bacteria has been partially characterized. We have located a cytidine 5'-diphospho-diacylglycerol:L-serine O-phosphatidyltransferase (phosphatidylserine synthase) activity in the membrane fraction of Bacillus licheniformis and Bacillus subtilis. The activity was demonstrated to be membrane associated by differential centrifugation, sucrose gradient centrifugation, and detergent solubilization. The direct involvement of cytidine 5'-diphospho-diacylglycerol in the reaction was demonstrated by the conversion of the liponucleotide phosphatidyl moiety to phosphatidylserine. This activity is dependent on divalent metal ion (manganese being optimal) and is stimulated by nonionic detergent and its product phosphatidylserine. Based on studies with various combinations of products and substrates, the reaction appears to follow a sequential BiBi kinetic mechanism.  相似文献   
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Adrenocorticotrophin secreting cells are identified in the hypophysis of the brown spiny mouseMus platythrix by conventional methods of light microscopy. Quantitative data showed that certain smaller acidophilic cells in thepars distalis, under conditions provoking their hypersecretion such as unilateral adrenalectomy and metopirone treatment, increase in number and size from the pre-existing corticotrophs. There is no evidence for the transmigration of these cells from the chromophobes, basophils or any other cell type. Thepars intermedia revealed two types of cells of which the type II cells are histochemically identical to adrenocorticotrophin secreting cells of thepars distalis  相似文献   
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A method for the genetic transformation of several citrus cultivars is described, including cultivars observed to be recalcitrant to conventional epicotyl-mediated transformation. Embryogenic cell suspension cultures, established from unfertilized ovules were used as target tissues for Agrobacterium-mediated transformation. Several modifications were made to the culture environment to investigate factors required for efficient transfer of the T-DNA and the subsequent regeneration of transgenic citrus plants. It was determined that co-cultivation of citrus cells and Agrobacterium in EME medium supplemented with maltose (EME-M) and 100 μM acetosyringone for 5 days at 25°C was optimum for transformation of each of the citrus cultivars. Efficient selection was obtained and escapes were prevented when the antibiotic hygromycin B was used as a selection antibiotic following transformation with an Agrobacterium strain containing hptII in the T-DNA region. Transgenic embryo regeneration and development was enhanced in medium that contained a liquid overlay consisting of a 1:2 mixture of 0.6 M BH3 and 0.15 M EME-M media. PCR and Southern blot analyses confirmed the presence of the T-DNA and the stable integration into the genome of regenerated plants, while RT-PCR demonstrated variable amounts of RNA being transcribed in different transgenic lines. This protocol can create an avenue for insertion of useful traits into any polyembryonic citrus cultivar that can be established as embryogenic cell suspension cultures, including popular specialty mandarins and seedless cultivars.  相似文献   
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