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61.
62.
R. Vijayalakshmi V. Subramanian Balachandran Unni Nair 《Journal of biomolecular structure & dynamics》2013,31(6):1063-1071
Abstract Molecular modeling and energy minimisation calculations have been used to investigate the interaction of chromium(III) complexes in different ligand environments with various sequences of B-DNA. The complexes are [Cr(salen)(H2O)2]+; salen denotes 1, 2 bis-salicylideneaminoethane, [Cr(salprn)(H2O)2]+; salprn denotes 1, 3 bis- salicylideneamino-propane, [Cr(phen)3]3+; phen denotes 1, 10 phenanthroline and [Cr(en)3]3+; en denotes eth- ylenediamine. All the chromium(III) complexes are interacted with the minor groove and major groove of d(AT)12, d(CGCGAATTCGCG)2 and d(GC)12 sequences of DNA. The binding energy and hydrogen bond parameters of DNA-Cr complex adduct in both the groove have been determined using molecular mechanics approach. The binding energy and formation of hydrogen bonds between chromium(III) complex and DNA has shown that all complexes of chromium(III) prefer minor groove interaction as the favourable binding mode. 相似文献
63.
Thankaraj Salammal Mariashibu Kondeti Subramanyam Muthukrishnan Arun Subramanian Mayavan Manoharan Rajesh Jeevaraj Theboral Markandan Manickavasagam Andy Ganapathi 《Acta Physiologiae Plantarum》2013,35(1):41-54
For the first time we have developed a reliable and efficient vacuum infiltration-assisted Agrobacterium-mediated genetic transformation (VIAAT) protocol for Indian soybean cultivars and recovered fertile transgenic soybean plants through somatic embryogenesis. Immature cotyledons were used as an explant and three Agrobacterium tumefaciens strains (EHA 101, EHA 105, and KYRT 1) harbouring the binary vector pCAMBIA1301 were experimented in the co-cultivation. The immature cotyledons were pre-cultured in liquid somatic embryo induction medium prior to vacuum infiltration with the Agrobacterium suspension and co-cultivated for 3 days on co-cultivation medium containing 50 mg l?1 citric acid, 100 µM acetosyringone, and 100 mg l?1 l-cysteine. The transformed somatic embryos were selected in liquid somatic embryo induction medium containing 10 mg l?1 hygromycin and the embryos were germinated in basal medium containing 20 mg l?1 hygromycin. The presence and integration of the hpt II and gus genes into the soybean genome were confirmed by GUS histochemical assay, polymerase chain reaction, and Southern hybridization. Among the different combinations tested, high transformation efficiency (9.45 %) was achieved when immature cotyledons of cv. Pusa 16 were pre-cultured for 18 h and vacuum infiltrated with Agrobacterium tumefaciens KYRT 1 for 2 min at 750 mm of Hg. Among six Indian soybean cultivars tested, Pusa 16 showed highest transformation efficiency of 9.45 %. The transformation efficiency of this method (VIAAT) was higher than previously reported sonication-assisted Agrobacterium-mediated transformation. These results suggest that an efficient Agrobacterium-mediated transformation protocol for stable integration of foreign genes into soybean has been developed. 相似文献
64.
AbstractThe objective of this study was to establish meaningful relationships between prokaryotic community profiles and water quality parameters in different water bodies (spring, stream, cave, and mine) in the middle reach of the Chesapeake & Ohio Canal National Historic Park (C&O), Maryland. The microbial profiles in the water samples were determined using metagenomic analysis. The relationships between microbial phylogenetic profiles and water quality parameters were investigated using principal component analysis (PCA) and redundancy analysis (RDA). The most abundant phyla identified in most samples were Proteobacteria (55.4%), Bacteroidetes (12.3%), Actinobacteria (10.6%), Firmicutes (2.4%), Planktomycetes (1.8%), Verrucomicrobia (1.5%), Chloroflexi (1.5%), and Acidobacteria (1.3%), which are major bacterial and archaeal groups typically observed in natural freshwater environments. PCA showed that water chemistry was determined primarily by the geology of the site and the type of water source (i.e., spring, stream, cave, or mine). Most samples located in carbonate formations correlated with high alkalinity, inorganic carbon, and calcium, representing the typical karstic geochemistry. RDA shows that pH, electrical conductivity, temperature and nutrients including nitrate, phosphate, and sulfate, were significant determinants of the microbial ecology. 相似文献
65.
Shivani Ahuja Nicole Jahr Sang-Choul Im Subramanian Vivekanandan Nataliya Popovych Stéphanie V. Le Clair Rui Huang Ronald Soong Jiadi Xu Kazutoshi Yamamoto Ravi P. Nanga Angela Bridges Lucy Waskell Ayyalusamy Ramamoorthy 《The Journal of biological chemistry》2013,288(30):22080-22095
Microsomal cytochrome b5 (cytb5) is a membrane-bound protein that modulates the catalytic activity of its redox partner, cytochrome P4502B4 (cytP450). Here, we report the first structure of full-length rabbit ferric microsomal cytb5 (16 kDa), incorporated in two different membrane mimetics (detergent micelles and lipid bicelles). Differential line broadening of the cytb5 NMR resonances and site-directed mutagenesis data were used to characterize the cytb5 interaction epitope recognized by ferric microsomal cytP450 (56 kDa). Subsequently, a data-driven docking algorithm, HADDOCK (high ambiguity driven biomolecular docking), was used to generate the structure of the complex between cytP4502B4 and cytb5 using experimentally derived restraints from NMR, mutagenesis, and the double mutant cycle data obtained on the full-length proteins. Our docking and experimental results point to the formation of a dynamic electron transfer complex between the acidic convex surface of cytb5 and the concave basic proximal surface of cytP4502B4. The majority of the binding energy for the complex is provided by interactions between residues on the C-helix and β-bulge of cytP450 and residues at the end of helix α4 of cytb5. The structure of the complex allows us to propose an interprotein electron transfer pathway involving the highly conserved Arg-125 on cytP450 serving as a salt bridge between the heme propionates of cytP450 and cytb5. We have also shown that the addition of a substrate to cytP450 likely strengthens the cytb5-cytP450 interaction. This study paves the way to obtaining valuable structural, functional, and dynamic information on membrane-bound complexes. 相似文献
66.
67.
Dhivya Subramanian Junqi Huang Mayalagu Sevugan Robert C. Robinson Mohan K. Balasubramanian Xie Tang 《Genetics》2013,194(2):435-446
Actin is a key cytoskeletal protein with multiple roles in cellular processes such as polarized growth, cytokinesis, endocytosis, and cell migration. Actin is present in all eukaryotes as highly dynamic filamentous structures, such as linear cables and branched filaments. Detailed investigation of the molecular role of actin in various processes has been hampered due to the multifunctionality of the protein and the lack of alleles defective in specific processes. The actin cytoskeleton of the fission yeast, Schizosaccharomyces pombe, has been extensively characterized and contains structures analogous to those in other cell types. In this study, primarily with the view to uncover actin function in cytokinesis, we generated a large bank of fission yeast actin mutants that affect the organization of distinct actin structures and/or discrete physiological functions of actin. Our screen identified 17 mutants with specific defects in cytokinesis. Some of these cytokinesis mutants helped in dissecting the function of specific actin structures during ring assembly. Further genetic analysis of some of these actin mutants revealed multiple genetic interactions with mutants previously known to affect the actomyosin ring assembly. We also characterize a mutant allele of actin that is suppressed upon overexpression of Cdc8p-tropomyosin, underscoring the utility of this mutant bank. Another 22 mutant alleles, defective in polarized growth and/or other functions of actin obtained from this screen, are also described in this article. This mutant bank should be a valuable resource to study the physiological and biochemical functions of actin. 相似文献
68.
Govindan Subramanian Shashidhar N. Rao 《Bioorganic & medicinal chemistry letters》2013,23(24):6667-6672
The performance of several structure-based design (SBD) approaches in predicting the binding affinity of diverse small molecule inhibitors co-crystallized to human renin was assessed to ascertain the modeling tool and method of choice required when dealing with structure-based lead optimization projects. Most of the SBD approaches investigated here were able to provide qualitative guidance, but quantitative accuracy as well as decisive discrimination between [in]actives is still not within reach. Such an outcome suggests that the current methods need improvement to capture the overall physics of the binding phenomenon for consistent applications in a lead optimization setting. 相似文献
69.
Mandy S. Wong Ling Chen Christopher Foster Radhika Kainthla Jerry W. Shay Woodring E. Wright 《Cell reports》2013,3(4):1028-1035
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70.
Filumena Maria Gomes S. V. Subramanian Ana Maria de Ulh?a Escobar Maria Helena Valente Sandra Josefina Ferraz Ellero Grisi Alexandra Brentani Günther Fink 《PloS one》2013,8(6)