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971.
Summary Four white-rot fungi isolated in Pakistan were used for decolorization of widely used reactive textile dyestuffs. Phanerochaete chrysosporium, Coriolus versicolor, Ganoderma lucidum and Pleurotus ostreatus were grown in defined nutrient media for decolorization of Drimarene Orange K-GL, Remazol Brilliant Yellow 3GL, Procion BluePX-5R and Cibacron Blue P-3RGR for 10 days in shake flasks. Samples were removed every day, centrifuged and the absorbances of the supernatants were read to determine percentage decolorization. It was observed that P. chrysosporium and C. versicolor could effectively decolorize Remazol Brilliant Yellow 3GL, Procion BluePX-5R and Cibacron Blue P-3RGR. Drimarene Orange K-GL was completely decolorized (0.2 g/l after 8 days) only by P.chrysosporium, followed by P. ostreatus (0.17 g/l after 10 days). P. ostreatus also showed good decolorization efficiencies (0.19–0.2 g/l) on all dyes except Remazol Brilliant Yellow (0.07 g/l after 10 days). G. lucidum did not decolorize any of the dyestuffs to an appreciable extent except Remazol Brilliant Yellow (0.2 g/l after 8 days).  相似文献   
972.
The possible use of xylanase from Aspergillus foetidus MTCC 4898 as a bread improver was tested in whole wheat bread. The partially purified xylanase was used as an additive at 12 U/g during mixing of wheat flour. The effects of xylanase addition on the fermentation stage and the final bread quality were analyzed. Remarkable decrease (11%) in water absorption and increase in dough rising (28.5%) were noticed. Final moisture content of the bread was higher (40.5%) than control (32.3%). Improvements in volume (53%) and specific volume (56%) were also significant. Sensory evaluation indicated better flavour, taste, softness and overall acceptability. Texture profile analysis confirmed the rheological changes. Firmness was decreased by more than four folds. Improvements in cohesiveness and decline in springiness and gumminess were observed.  相似文献   
973.
Analogues of parthenin were synthesized by substitutions at different reaction centres to establish a structure–activity relationship (SAR). Some of the molecules have displayed significant cytotoxicity in human cervical carcinoma (HeLa) and human myeloid leukemia (HL-60) cells. A few of the compounds also induced apoptosis in HL-60 cells measured in terms of sub-Go/G1 DNA fraction. Also one of the lead molecules has been shown to be the inhibitor of both telomerase and topoisomerase-II.  相似文献   
974.
We report herein the design and synthesis of 4-(benzimidazol-2-yl)-1,2,5-oxadiazol-3-amine derivatives as inhibitors of p70S6 kinase. Screening hits containing the 4-(benzimidazol-2-yl)-1,2,5-oxadiazol-3-ylamine scaffold were optimized for p70S6K potency and selectivity against related kinases. Structure-based design employing an active site homology model derived from PKA led to the preparation of benzimidazole 5-substituted compounds 26 and 27 as highly potent inhibitors (Ki <1 nM) of p70S6K, with >100-fold selectivity against PKA, ROCK and GSK3.  相似文献   
975.
976.
We report here two cases of trisomy 13 in acute myeloid leukemia M1 subtype. short-term unstimulated bone marrow and peripheral blood lymphocyte culture showed 47, XY, +13 in all metaphase plates and trisomy 13 was confirmed with whole chromosome paint probes. Trisomy 13 in AML-M1 is a rare numerical abnormality. This is the first Indian report of sole trisomy 13 in AML-M1. Here, we present two cases of elder male patients, which may constitute a distinct subtype.  相似文献   
977.
978.
979.
The acyl‐AMP forming family of adenylating enzymes catalyze two‐step reactions to activate a carboxylate with the chemical energy derived from ATP hydrolysis. X‐ray crystal structures have been determined for multiple members of this family and, together with biochemical studies, provide insights into the active site and catalytic mechanisms used by these enzymes. These studies have shown that the enzymes use a domain rotation of 140° to reconfigure a single active site to catalyze the two partial reactions. We present here the crystal structure of a new medium chain acyl‐CoA synthetase from Methanosarcina acetivorans. The binding pocket for the three substrates is analyzed, with many conserved residues present in the AMP binding pocket. The CoA binding pocket is compared to the pockets of both acetyl‐CoA synthetase and 4‐chlorobenzoate:CoA ligase. Most interestingly, the acyl‐binding pocket of the new structure is compared with other acyl‐ and aryl‐CoA synthetases. A comparison of the acyl‐binding pocket of the acyl‐CoA synthetase from M. acetivorans with other structures identifies a shallow pocket that is used to bind the medium chain carboxylates. These insights emphasize the high sequence and structural diversity among this family in the area of the acyl‐binding pocket. Proteins 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
980.
The influence of 15 commercially available fungicides on the germination, growth and virulence of Metarhizium anisopliae, Beauveria bassiana, Isaria fumosorosea, and Lecanillium longisporum was evaluated. The influence of the fungicides on conidial germination was dependant on the fungicide type and dose. Most fungicides retarded conidial germination of all the fungi tested at 10× and at the recommended rate of application, however, their toxicity declined at lower concentrations. Most of the fungicides inhibited mycelial growth of B. bassiana, whereas L. longisporum growth was unaffected. Only two and eight fungicides influenced mycelial growth of I. fumosorosea and M. anisopliae, respectively. None of the fungicides influenced the virulence of B. bassiana and L. longisporum, however, tolylfluanid and azoxystrobin reduced the virulence of M. anisopliae and I. fumosorosea, respectively. These studies clearly show that certain fungicides have the potential to inhibit germination of entomopathogenic fungi in vitro but appear to have little or no effect on their virulence against target insects.  相似文献   
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