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351.
Nishad Jyoti Panda Alok Kumar Chowrasia Soni Nirmala Chongtham Mondal Tapan Kumar 《Journal of plant biochemistry and biotechnology.》2022,31(4):953-960
Journal of Plant Biochemistry and Biotechnology - Salinity affects plant in a variety of ways, including ion toxicity, osmotic stress and oxidative damage. Allantoin is a nitrogenous compound... 相似文献
352.
Ying Cheng Adriana Ayres Pedroso Steffen Porwollik Michael McClelland Margie D. Lee Tiffany Kwan Katherine Zamperini Vivek Soni Holly S. Sellers Scott M. Russell John J. Maurer 《Applied and environmental microbiology》2015,81(2):502-514
Salmonella enterica serovar Kentucky has become the most frequently isolated serovar from poultry in the United States over the past decade. Despite its prevalence in poultry, it causes few human illnesses in the United States. The dominance of S. Kentucky in poultry does not appear to be due to single introduction of a clonal strain, and its reduced virulence appears to correlate with the absence of virulence genes grvA, sseI, sopE, and sodC1. S. Kentucky''s prevalence in poultry is possibly attributable to its metabolic adaptation to the chicken cecum. While there were no difference in the growth rate of S. Kentucky and S. Typhimurium grown microaerophilically in cecal contents, S. Kentucky persisted longer when chickens were coinfected with S. Typhimurium. The in vivo advantage that S. Kentucky has over S. Typhimurium appears to be due to differential regulation of core Salmonella genes via the stationary-phase sigma factor rpoS. Microarray analysis of Salmonella grown in cecal contents in vitro identified several metabolic genes and motility and adherence genes that are differentially activated in S. Kentucky. The contributions of four of these operons (mgl, prp, nar, and csg) to Salmonella colonization in chickens were assessed. Deletion of mgl and csg reduced S. Kentucky persistence in competition studies in chickens infected with wild-type or mutant strains. Subtle mutations affecting differential regulation of core Salmonella genes appear to be important in Salmonella''s adaptation to its animal host and especially for S. Kentucky''s emergence as the dominant serovar in poultry. 相似文献
353.
The deposition of silicon in tissues of the inflorescence bracts of rice has been studied with the electron probe microanalyzer. Tissues for analysis were prepared by means of peels, frozen transverse and longitudinal sections, chromations and macerations. The microanalysis shows the heaviest deposition in a layer external to the abaxial (outer) epidermis. The cells of this epidermis are only sparsely silicified, but the’ imprints of these cells are left on the outer silica layer. In the inner tissues of the bracts, silicon deposition is mostly associated with the cell walls. 相似文献
354.
Soni Surabhi Sathe Sneha S. Odaneth Annamma A. Lali Arvind M. Chandrayan Sanjeev K. 《Extremophiles : life under extreme conditions》2017,21(4):687-697
Extremophiles - Caldicellulosiruptor bescii, the most thermophilic cellulolytic bacterium, is rich in hydrolytic and accessory enzymes that can degrade untreated biomass, but the precise role of... 相似文献
355.
Xanthomonas axonopodis pv. punicae(Xap)causing bacterial blight is an important pathogen that incurs significant losses to the exportability of pomegranate. Xap uses the Xop TTSS-effector, via the type three secretion system, to suppress pomegranate immunity. Here, we investigate the role of XopL during blight pathogenesis.We observed that XopL is essential for its in planta growth and full virulence. Leaves inoculated with Xap DxopL produced restricted water-soaked lesions compared to those inoculated with wild-type Xap. XopL supports Xap for its sustained multiplication in pomegranate by suppressing the plant cel death(PCD) event. We further demonstrated that XopL suppresses immune responses, such as callose deposition and production of reactive oxygen species(ROS). RT-qPCR analysis revealed that immune responsive genes were upregulated when challenged with Xap DxopL,whereas upregulation of such genes was compromised in the complemented strain containing the xopL gene. The transiently expressed XopL ::EYFP fusion protein was localized to the plasma membrane, indicating the possible site of its action. Altogether, this study highlights that XopL is an important TTSS-effector of Xap that suppresses plant immune responses, including PCD, presumably to support the multiplication of Xap for a sufficient time-period during blight disease development. 相似文献
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Benu Sethi Monika Jain Manish Chowdhary Yogesh Soni Yukti Bhatia Vikram Sahai Saroj Mishra 《Biotechnology and Bioprocess Engineering》2002,7(1):43-51
The cloning and expression of β-glucosidase II, encoded by the geneßglu2, from thermotolerant yeastPichia etchellsii intoEscherichia coli is described. Cloning of the 7.3 kbBamHI/SalI yeast insert containingßglu2 in pUC18, which allowed for reverse orientation of the insert, resulted in better enzyme expression. Transformation of this plasmid intoE. coli JM109 resulted in accumulation of the enzyme in periplasmic space. At 50°C, the highest hydrolytic activity of 1686 IU/g protein was obtained on sophorose. Batch and fed-batch techniques were employed for enzyme production in a 14 L bioreactor. Exponential feeding rates were determined from mass balance equations and these were employed to control specific growth rate and in turn maximize cell growth and enzyme production. Media optimization coupled with this strategy resulted in increased enzyme units of 1.2 kU/L at a stabilized growth rate of 0.14 h?1. Increased enzyme production in bioreactor was accompanied by formation of inclusion bodies. 相似文献
359.
Plasmonics - Nanoparticles are of potential use for therapeutic applications, and nowadays a variety of modalities involving optical characteristics of nanoparticles are in the clinical translation... 相似文献
360.