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181.
Shailender Kumar Verma Satish Kumar Imran Sheikh Prachi Sharma Priyanka Mathpal Sachin Malik Priyanka Kundu Anjali Awasthi Sundip Kumar Ramasare Prasad Harcharan Singh Dhaliwal 《Plant Molecular Biology Reporter》2016,34(6):1083-1094
Biofortification of bread wheat by the transfer of useful variability of high grain Fe and Zn from Aegilops kotschyi through induced homoeologous pairing is the most feasible approach to alleviate micronutrient malnutrition worldwide. Deficiency of chromosome 5B in interspecific hybrids allows homoeologous pairing and recombination of chromosomes of wheat with those of the related species. The interspecific hybrid plants without 5B chromosome showed much higher chromosome pairing than did the plants with 5B. The F1 plants without 5B chromosome were selected and repeatedly backcrossed with wheat cultivar PBW343. The chromosome number of BC2F1 plants ranged from 43 to 60 with several univalents and multivalents. Molecular markers and GISH analysis confirmed the introgression of U/S chromosomes of Ae. kotschyi and their fragments in wheat. The BC2F2 plants showed up to 125 % increase in Fe and 158 % increase in Zn compared to PBW343 with Lr24 and Yr36. Induced homoeologous pairing in the absence of 5B was found to be an effective approach for transfer of useful variability for enhanced grain Fe and Zn content for biofortification of wheat for high grain micronutrient content. 相似文献
182.
Sunil Kumar Narwal Nitin Kumar Saun Priyanka Dogra Reena Gupta 《Russian Journal of Bioorganic Chemistry》2016,42(1):69-73
Isoamyl acetate, a pear or banana flavor, is widely used in food, beverage, cosmetic, and pharmaceutical industries. In the present work, lipase from Bacillus aerius was immobilized on silica gel matrix in the presence of a cross-linking agent, glutaraldehyde, and its efficiency in synthesizing isoamyl acetate using esterification reaction was studied. The esterification of acetic acid and isoamyl alcohol by silica-bound lipase was studied as a function of time and temperatures. The incubation time of 10 h, temperature of 55°C, substrate molar ratio 1: 1, and the amount of lipase as 1% were found to be optimal for the esterification reaction. The bound lipase catalyzed the esterification of acetic acid by isoamyl alcohol with the yield of about 68% under the optimized reaction conditions. The product was identified as isoamyl acetate using gas-liquid chromatography, nuclear magnetic resonance, and Fourier transform IR spectroscopy analysis by the presence of an ester group at the wavenumber of 1720.5 cm–1. 相似文献
183.
Chitrangada Dash Sukanti Bala Mohapatra Prasanta Kumar Maiti 《Preparative biochemistry & biotechnology》2016,46(1):1-7
Actinobacteria are promising source of a wide range of important enzymes, some of which are produced in industrial scale, with others yet to be harnessed. L-Asparaginase is used as an antineoplastic agent. The present work deals with the production and optimization of L-asparaginase from Actinomycetales bacterium BkSoiiA using submerged fermentation in M9 medium. Production optimization resulted in a modified M9 medium with yeast extract and fructose as carbon and nitrogen sources, respectively, at pH 8.0, incubated for 120 hr at 30 ± 2°C. The crude enzyme was purified to near homogeneity by ammonium sulfate precipitation following dialysis, ion-exchange column chromatography, and finally gel filtration. The sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) revealed an apparent molecular weight of 57 kD. The enzyme was purified 95.06-fold and showed a final specific activity of 204.37 U/mg with 3.49% yield. The purified enzyme showed maximum activity at a pH 10.0 and was stable at pH 7.0 to 9.0. The enzyme was activated by Mn2+ and strongly inhibited by Ba2+. All these preliminary characterization suggests that the L-asparaginase from the source may be a tool useful to pharmaceutical industries after further research. 相似文献
184.
185.
The C-terminus of Hsp70 interacting protein (CHIP) is being considered to be a cellular quality control E3 ubiquitin ligase because of its ability to degrade misfolded proteins in association with heat shock chaperones. The neuroprotective role of CHIP also has been implicated in several familial neurodegenerative diseases including polyglutamine diseases. However, the regulation of the expression of CHIP under different stress conditions and its protective role thereon is unknown. Here we have shown that the mRNA level of CHIP is significantly increased in the cells exposed to oxidative, endoplasmic reticulum and proteasomal stress. CHIP also protected from various stress-induced cell death. Finally, we have demonstrated upregulation of CHIP mRNA levels in the expanded polyglutamine protein expressing cells. Our result suggests that the upregulation of CHIP under various stress environments is an adaptive response of the cells to deal with the excess burden of misfolded protein. 相似文献
186.
Indu B. Maiti Carol Von Lanken Yiling Hong Nrisingha Dey Arthur G. Hunt 《Journal of plant biochemistry and biotechnology.》1999,8(2):67-73
Plants can be protected against infection by potyviruses by expressing different portions of potyviral genomes as transgenes. This strategy has proven effective with several potyvirus genes, including the Nla, Nlb, and coat protein coding regions. Given the effectiveness of separate potyvirus coding regions as determinants of resistance, we tested the hypothesis that combinations of potyvirus coding regions would provide additively greater protection of plants against potyviruses. For this, we compared transgenic plant lines that expressed either the coat protein (CP) or the Nla+Nlb+coat protein (NNC) coding regions from tobacco vein mottling virus (TVMV). We found that plants that carry the NNC gene combination were invariably less resistant to TVMV than were lines that contain a CP gene alone. Additionally, we found that NNC lines displayed virtually no resistance to tobacco etch virus (TEV), in contrast to the CP lines. We conclude that combining more than one virus-derived resistance determinant in a single construct is detrimental to the production of virus-resistant plants. 相似文献
187.
Abdul Aziz Ali Dhrubajyoti Gogoi Amrita K. Chaliha Alak K. Buragohain Priyanka Trivedi Prakash J. Saikia Praveen S. Gehlot Arvind Kumar Vinita Chaturvedi Diganta Sarma 《Bioorganic & medicinal chemistry letters》2017,27(16):3698-3703
A library of seventeen novel 1,2,3-triazole derivatives were efficiently synthesized in excellent yields by the popular ‘click chemistry’ approach and evaluated in vitro for their anti-tubercular activity against Mycobacterium tuberculosis H37Ra (ATCC 25177 strain). Among the series, six compounds exhibited significant activity with minimum inhibitory concentration (MIC) values ranging from 3.12 to 0.78 μg/mL and along with no significant cytotoxicity against MBMDMQs (mouse bone marrow derived macrophages). Molecular docking of the target compounds into the active site of DprE1 (Decaprenylphosphoryl-β-d-ribose-2′-epimerase) enzyme revealed noteworthy information on the plausible binding interactions. 相似文献
188.
Priyanka?Varun S.?A.?Ranade Sangeeta?SaxenaEmail authorView authors OrcID profile
return OK on get 《Protoplasma》2017,254(6):2055-2070
Papaya leaf curl disease (PaLCuD) caused by papaya leaf curl virus (PaLCuV) not only affects yield but also plant growth and fruit size and quality of papaya and is one of the most damaging and economically important disease. Management of PaLCuV is a challenging task due to diversity of viral strains, the alternate hosts, and the genomic complexities of the viruses. Several management strategies currently used by plant virologists to broadly control or eliminate the viruses have been discussed. In the absence of such strategies in the case of PaLCuV at present, the few available options to control the disease include methods like removal of affected plants from the field, insecticide treatments against the insect vector (Bemisia tabaci), and gene-specific control through transgenic constructs. This review presents the current understanding of papaya leaf curl disease, genomic components including satellite DNA associated with the virus, wide host and vector range, and management of the disease and suggests possible generic resistance strategies. 相似文献
189.
In this study, Bacillus pumilus SE34 and B. pumilus T4 were combined with Bacillus subtilis GBO3, B. pumilus INR7 and Pseudomonas fluorescens UOM14 to form COM1, COM2 and COM3, respectively. All combinations were used to find their synergistic effect on Moringa oleifera for growth promotion and Fe accumulation efficiency in foliage. The results indicate a significant increase in Fe content in foliage using COM3 (405.70%) followed by COM2 (105.83%) in comparison to the control with a simultaneous decrease in the soil Fe content. Increased expression of iron-transport-related genes like iron-phytosiderophore oligopeptide transporter and natural-resistance-associated macrophage protein, in foliage of Moringa using real-time PCR correlates with the enriched iron content in foliage of treated plants. Increase in citric acid was in direct relation to the Fe accumulation in foliage. Growth promotion and Fe enhancement using plant-growth-promoting rhizobacteria’s combination was significantly higher, proving its synergistic effect as a great source for sustainable development in agriculture and nutrition. 相似文献
190.
Dopamine oxidation products such as H2O2 and reactive quinones have been held responsible for various toxic actions of dopamine, which have implications in the aetiopathogenesis of Parkinson's disease. This study has shown that N-acetylcysteine (0.25-1 mm) is a potent scavenger of both H2O2 and toxic quinones derived from dopamine and it further prevents dopamine mediated inhibition of Na+,K+-ATPase activity and mitochondrial respiratory chain function. The quinone scavenging ability of N-acetylcysteine is presumably related to its protective effect against dopamine mediated inhibition of mitochondrial respiratory chain activity. However, both H2O2 scavenging and quinone scavenging properties of N-acetylcysteine probably account for its protective effect against Na+,K+-ATPase inhibition induced by dopamine. The results have important implications in the neuroprotective therapy of sporadic Parkinson's disease since inactivation of mitochondrial respiratory activity and Na+,K+-ATPase may trigger intracellular damage pathways leading to the death of nigral dopaminergic neurons. 相似文献