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71.
Subhojit Chakraborty Rishi Gupta Kavish Kumar Jain Ramesh Chander Kuhad 《Bioprocess and biosystems engineering》2016,39(11):1659-1670
Trichoderma sp. is a potential cellulase producing mesophilic fungi which grow under mild acidic condition. In this study, growth and nutritional conditions were manipulated for the maximum and cost-effective production of cellulase using lab strain Trichoderma sp. RCK65 and checked for its efficiency in hydrolysis of Prosopis juliflora (a woody substrate). Preliminary studies suggested that when 48 h old secondary fungal culture (20 % v/w) was inoculated in wheat bran moistened with mineral salt solution (pH 4.5 and 1:3 solid to moisture ratio), incubated at 30 °C and after 72 h, it produced maximum cellulase (CMCase 145 U/gds, FPase 38 U/gds and β-glucosidase 105 U/gds). However, using statistical approach a S:L ratio (1:1) was surprisingly found to be optimum that improved cellulase that is CMCase activity by 6.21 %, FPase activity by 23.68 % and β-glucosidase activity by 37.28 %. The estimated cost of crude enzyme (Rs. 5.311/1000 FPase units) seems to be economically feasible which may be due to high enzyme titre, less cultivation time and low media cost. Moreover, when the crude enzyme was used to saccharify pretreated Prosopis juliflora (a woody substrate), it resulted up to 83 % (w/w) saccharification. 相似文献
72.
Sushma Rishi V. K. Agarwal G. R. Anand S. P. Agarwal D. S. Balaine P. K. Dwaraknath 《Biochemical genetics》1981,19(9-10):987-996
Serum guanase levels of Indian Zebu (Hariana) cattle and its crosses with different exotic levels of temperate breeds of dairy cattle were estimated in 527 animals, and their associations with economic characters were determined. The overall mean value of serum guanase level was 13.46±0.45 IU/ml of serum. An inverse relationship between the concentration of the enzyme and the frequency of cattle falling within a definite range was observed, as over 75% of the animals possessed 1 to 20 IU/ml of serum guanase. An analysis of variance revealed significant differences (P<0.01) in enzyme levels among different genetic groups under study. Hariana (Zebu) purebreds had significantly higher enzyme levels (19.60±1.85) than any of the crossbred groups, whose enzyme levels ranged from 8.99±1.41 in Red Dane F1 half-breds to 14.30±1.11 in Brown Swiss F1 half-breds. The correlation and regression coefficients were significantly positive for reproductive traits such as age at first service and age at first calving, and significantly negative for production traits such as lactation yield and lactation length. These results suggest that selection of dairy cattle based on low serum guanase levels might result in correlated improvements in dairy cattle productivity. 相似文献
73.
Rishi G. Vaswani Agenor Limon Jorge Mauricio Reyes-Ruiz Ricardo Miledi A. Richard Chamberlin 《Bioorganic & medicinal chemistry letters》2009,19(1):132-135
The design and synthesis of four pyrrolidine scaffolds that are structurally related to the known ionotropic glutamate receptor antagonist, (?)-kaitocephalin, is described. Additionally, preliminary results of the biological evaluation of these compounds are disclosed. 相似文献
74.
Eric Newberry Rishi Bhandari Joseph Kemble Edward Sikora Neha Potnis 《Environmental microbiology》2020,22(7):2693-2708
Assessment of pathogen diversity in agricultural fields is essential for informing management decisions and the development of resistant plant varieties. However, many population genomic studies have relied on culture-based approaches that do not provide quantitative assessment of pathogen populations at the field-level or the associated host microbiome. Here, we applied whole-genome shotgun sequencing of microbial DNA extracted directly from the washings of pooled leaf samples, collected from individual tomato and pepper fields in Alabama that displayed the classical symptoms of bacterial spot disease caused by Xanthomonas spp. Our results revealed that while the occurrence of both X. perforans and X. euvesicatoria within fields was limited, evidence of co-occurrence of up to three distinct X. perforans genotypes was obtained in 7 of 10 tomato fields sampled. These population dynamics were accompanied by the corresponding type 3 secreted effector repertoires associated with the co-occurring X. perforans genotypes, indicating that metapopulation structure within fields should be considered when assessing the adaptive potential of X. perforans. Finally, analysis of microbial community composition revealed that co-occurrence of the bacterial spot pathogens Pseudomonas cichorii and Xanthomonas spp. is common in Alabama fields and provided evidence for the non-random association of several other human and plant opportunists. 相似文献
75.
76.
Kamaluddin Rishi Muni Singh Malik Zainul Abdin Mather Ali Khan Tanweer Alam Salim Khan Lal Chand Prasad Arun Kumar Joshi 《Journal of Plant Biology》2007,50(4):504-507
To understand the genetic control of grain filling duration (GFD), i.e., the number of days from anthesis to physiological
maturity, we studied the F1, F2, BC1 and BC2 generations of six spring wheat crosses from nine varieties/genotypes. Generation mean analysis for gene effects indicated
that one or more types of epistasis were significant in all crosses. In each pairing, the F1 and F2 means were either intermediate or closer to the mean of the parent having the longer GFD. Our narrow-sense heritability estimate
was reasonably high, at 47.67 (based on diallel analysis). This demonstrated that progress could be made from the selection
in these crosses for either long or short GFD. The two early varieties that had identical maturity durations differed in their
GFD values, indicating that maturity dates are not good criteria when choosing parents for modifying GFD. To utilize favorable
additive × additive effects during this selection, we suggest that a single seed descent (SSD) or bulk popula-tion approach
be adopted. In comparison, dominance effects would prove quite useful in hybrid wheat breeding programs. 相似文献
77.
Assessment of phytotoxicity of anthracene in soybean (Glycine max) with a quick method of chlorophyll fluorescence 下载免费PDF全文
A decrease in photosynthetic efficiency may indicate the toxic effects of environmental pollutants on higher plants. Measurement of chlorophyll (Chl) a fluorescence to assess the performance of photosystem II (PSII) was used as an bioindicator of toxicity of the polycyclic aromatic hydrocarbon (PAH) anthracene (ANT) in soybean plants. The results revealed that ANT treatment caused a reduction in quantum yield of PSII, damage to the oxygen evolving complex, as well as a significant reduction in performance index of PSII. However, change in performance index was more prominent, and it seems that the performance index is a more sensitive parameter to environmental contaminants. Moreover, a change in heterogeneity of PSII was also observed. The number of active reaction centres decreased with increasing concentration of ANT, as secondary plastoquinone reducing centres were converted into non‐reducing centres, and PSIIα centres were converted into PSIIβ and PSIIγ centres. The influence of ANT on PSII heterogeneity could be an important reason for reductions in the PSII performance. 相似文献
78.
Changes in the conformation of spinach thylakoid membranes were monitored in 5-doxyl stearic acid (SAL)-treated thylakoid
membranes in the presence of various anions (Cl−, Br−, I−, NO2
−, SO4
2−, PO4
3−). The presence of anions made the thylakoid membrane more fluid. The extent of change in membrane fluidity differed with
different anion and was reversible. 相似文献
79.
Various pathogens including Salmonella species are known to induce apoptosis in host cell types during their infection processes. However, the bacterial components capable of inducing apoptosis have not been fully understood. It is now known that in vivo expression of virulence determinants differ from the expression under in vitro conditions. Therefore, in the present study, attempts were made to evaluate the apoptotic potential of outer-membrane protein (OMP) from short-chain fatty acids (SCFA) exposed Salmonella enterica serovar Typhi. Short-chain fatty acids exposure is one of the in vivo stresses encountered by the pathogen in the intestine. Therefore, to simulate the in vivo condition, S. enterica serovar Typhi was grown in the presence of SCFA and its OMP profile was analyzed. The apoptotic potential of 55 kDa protein expressed with enhanced intensity under the SCFA stress was evaluated. Murine peritoneal macrophages interacted with 55 kDa protein showed DNA fragmentation, changes in fluorescence and exposure of phosphatidylserine on their outer leaflets. Levels of nitrite and citrulline were found to be increased in the supernatant of macrophages after interacting them with 55 kDa protein. However, the enzymatic activity of superoxide dismutase was found to be decreased as compared to that of the control (uninteracted) macrophages. These observations indicate that increased levels of nitrite and decreased levels of superoxide dismutase may be one of the mechanisms to induce apoptosis in macrophages by SCFA induced 55 kDa OMP. These findings may help us better understand the pathophysiology of the disease during the host pathogen interactions. 相似文献
80.
We present the thermal stability monitored by circular dichroism (CD) spectroscopy at 222 nm of 100 heterodimers that contain all possible coiled-coil a-a' pairs for 10 amino acids (I, V, L, N, A, K S, T, E, and R). This includes the stability of 36 heterodimers for 6 amino acids (I, V, L, N, A, and K) previously described and 64 new heterodimers including the 4 amino acids (S, T, E, and R). We have calculated a double mutant alanine thermodynamic cycle to determine a-a' pair coupling energies to evaluate which a-a' pairs encourage specific dimerization partners. The four new homotypic a-a' pairs (T-T, S-S, R-R, E-E) are repulsive relative to A-A and have destabilizing coupling energies. Among the 90 heterotypic a-a' pairs, the stabilizing coupling energies contain lysine or arginine paired with either an aliphatic or a polar amino acid. The range in coupling energies for each amino acid reveals its potential to regulate dimerization specificity. The a-a' pairs containing isoleucine and asparagine have the greatest range in coupling energies and thus contribute dramatically to dimerization specificity, which is to encourage homodimerization. In contrast, the a-a' pairs containing charged amino acids (K, R, and E) show the least range in coupling energies and promiscuously encourage heterodimerization. 相似文献