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81.
Theerawitaya Cattarin Tisarum Rujira Samphumphuang Thapanee Singh Harminder Pal Takabe Teruhiro Cha-um Suriyan 《Protoplasma》2020,257(2):525-536
Protoplasma - Sugarcane is a sugar-producing crop widely grown in tropical regions in over 120 countries of the world. Salt-affected soil is one of the most significant abiotic constraints that... 相似文献
82.
Nonstructural proteins 7 and 8 of feline coronavirus form a 2:1 heterotrimer that exhibits primer-independent RNA polymerase activity 总被引:1,自引:0,他引:1
Xiao Y Ma Q Restle T Shang W Svergun DI Ponnusamy R Sczakiel G Hilgenfeld R 《Journal of virology》2012,86(8):4444-4454
Nonstructural proteins 7 and 8 of severe acute respiratory syndrome coronavirus (SARS-CoV) have previously been shown by X-ray crystallography to form an 8:8 hexadecamer. In addition, it has been demonstrated that N-terminally His6-tagged SARS-CoV Nsp8 is a primase able to synthesize RNA oligonucleotides with a length of up to 6 nucleotides. We present here the 2.6-Å crystal structure of the feline coronavirus (FCoV) Nsp7:Nsp8 complex, which is a 2:1 heterotrimer containing two copies of the α-helical Nsp7 with conformational differences between them, and one copy of Nsp8 that consists of an α/β domain and a long-α-helix domain. The same stoichiometry is found for the Nsp7:Nsp8 complex in solution, as demonstrated by chemical cross-linking, size exclusion chromatography, and small-angle X-ray scattering. Furthermore, we show that FCoV Nsp8, like its SARS-CoV counterpart, is able to synthesize short oligoribonucleotides of up to 6 nucleotides in length when carrying an N-terminal His6 tag. Remarkably, the same protein harboring the sequence GPLG instead of the His6 tag at its N terminus exhibits a substantially increased, primer-independent RNA polymerase activity. Upon addition of Nsp7, the RNA polymerase activity is further enhanced so that RNA up to template length (67 nucleotides) can be synthesized. Further, we show that the unprocessed intermediate polyprotein Nsp7-10 of human coronavirus (HCoV) 229E is also capable of synthesizing oligoribonucleotides up to a chain length of six. These results indicate that in case of FCoV as well as of HCoV 229E, the formation of a hexadecameric Nsp7:Nsp8 complex is not necessary for RNA polymerase activity. Further, the FCoV Nsp7:Nsp8 complex functions as a noncanonical RNA polymerase capable of synthesizing RNA of up to template length. 相似文献
83.
Ponnusamy M Liu N Sellamuthu R Zhao TC Mao H Zhuang S 《American journal of physiology. Renal physiology》2012,303(1):F83-F91
We recently reported that necrotic renal proximal tubular cells (RPTC) can induce the death of renal interstitial fibroblasts. Since autophagy plays either cytoprotective or cytodestructive roles depending on the experimental condition, the present study was carried out to investigate whether necrotic RPTC would induce autophagy of renal interstitial fibroblasts and, if so, whether autophagy would contribute to cell death or exert a protective effect. Exposure of necrotic RPTC supernatant (RPTC-Sup) induced autophagy in renal interstitial fibroblast cells (NRK-49F) in a time- and dose-dependent manner, and its induction was earlier than caspase-3 activation. Inhibition of autophagy with 3-methyladenine (3-MA) or knockdown of Beclin-1, a molecule involved in the initiation of autophagosome formation, with small interference RNA (siRNA) significantly enhanced necrotic RPTC-Sup-induced cell death. Necrotic RPTC-Sup induced phosphorylation of extracellular signal-regulated kinases (ERK1/2), p38, c-Jun NH(2)-terminal kinases (JNKs), and AKT. Treatment with an ERK1/2 pathway inhibitor, but not with specific inhibitors for p38, JNKs, or AKT pathways, blocked NRK-49F autophagy and cell death upon exposure to necrotic RPTC-Sup. Furthermore, knockdown of MEK1 with siRNA also reduced autophagy along with cell death in NRK-49F exposed to necrotic RPTC-Sup. In contrast, overexpression of MEK1/2 increased RPTC-Sup-induced fibroblast cell death without enhancing autophagy. Collectively, this study demonstrates that necrotic RPTC induce both autophagy and cell death and that autophagy plays a cytoprotective or prosurvival role in renal fibroblasts. Furthermore, necrotic RPTC-induced autophagy and cell death in renal fibroblasts is mediated by the activation of the MEK1-ERK1/2 signaling pathway. 相似文献
84.
Thirteen pink-pigmented facultative methylotrophic (PPFM) strains isolated from Adyar and Cooum rivers in Chennai and forest
soil samples in Tamil Nadu, India, along with Methylobacterium extorquens, M. organophilum, M. gregans, and M. komagatae were screened for phosphate solubilization in plates. P-solubilization index of the PPFMs grown on NBRIP—BPB plates for 7 days
ranged from 1.1 to 2.7. The growth of PPFMs in tricalcium phosphate amended media was found directly proportional to the glucose
concentration. Higher phosphate solubilization was observed in four strains MSF 32 (415 mg l−l), MDW 80 (301 mg l−l), M. komagatae (279 mg l−l), and MSF 34 (202 mg l−l), after 7 days of incubation. A drop in the media pH from 6.6 to 3.4 was associated with an increase in titratable acidity.
Acid phosphatase activity was more pronounced in the culture filtrate than alkaline phosphatase activity. Adherence of phosphate
to densely grown bacterial surface was observed under scanning electron microscope after 7-day-old cultures. Biochemical characterization
and screening for methanol dehydrogenase gene (mxaF) confirmed the strains as methylotrophs. The mxaF gene sequence from MSF 32 clustered towards M.
lusitanum sp. with 99% similarity. This study forms the first detailed report on phosphate solubilization by the PPFMs. 相似文献
85.
86.
Sen M Shah B Rakshit S Singh V Padmanabhan B Ponnusamy M Pari K Vishwakarma R Nandi D Sadhale PP 《PLoS pathogens》2011,7(11):e1002384
Candida albicans, a human fungal pathogen, undergoes morphogenetic changes that are associated with virulence. We report here that GAL102 in C. albicans encodes a homolog of dTDP-glucose 4,6-dehydratase, an enzyme that affects cell wall properties as well as virulence of many pathogenic bacteria. We found that GAL102 deletion leads to greater sensitivity to antifungal drugs and cell wall destabilizing agents like Calcofluor white and Congo red. The mutant also formed biofilms consisting mainly of hyphal cells that show less turgor. The NMR analysis of cell wall mannans of gal102 deletion strain revealed that a major constituent of mannan is missing and the phosphomannan component known to affect virulence is greatly reduced. We also observed that there was a substantial reduction in the expression of genes involved in biofilm formation but increase in the expression of genes encoding glycosylphosphatidylinositol-anchored proteins in the mutant. These, along with altered mannosylation of cell wall proteins together might be responsible for multiple phenotypes displayed by the mutant. Finally, the mutant was unable to grow in the presence of resident peritoneal macrophages and elicited a weak pro-inflammatory cytokine response in vitro. Similarly, this mutant elicited a poor serum pro-inflammatory cytokine response as judged by IFNγ and TNFα levels and showed reduced virulence in a mouse model of systemic candidiasis. Importantly, an Ala substitution for a conserved Lys residue in the active site motif YXXXK, that abrogates the enzyme activity also showed reduced virulence and increased filamentation similar to the gal102 deletion strain. Since inactivating the enzyme encoded by GAL102 makes the cells sensitive to antifungal drugs and reduces its virulence, it can serve as a potential drug target in combination therapies for C. albicans and related pathogens. 相似文献
87.
Rupali Chopra Shafat Ali Amit K. Srivastava Shweta Aggarwal Bhupender Kumar Siddharth Manvati Ponnusamy Kalaiarasan Mamta Jena Vijay K. Garg Sambit N. Bhattacharya Rameshwar N. K. Bamezai 《PLoS genetics》2013,9(7)
Leprosy is a chronic infectious disease caused by Mycobacterium Leprae, where the host genetic background plays an important role toward the disease pathogenesis. Various studies have identified a number of human genes in association with leprosy or its clinical forms. However, non-replication of results has hinted at the heterogeneity among associations between different population groups, which could be due to differently evolved LD structures and differential frequencies of SNPs within the studied regions of the genome. A need for systematic and saturated mapping of the associated regions with the disease is warranted to unravel the observed heterogeneity in different populations. Mapping of the PARK2 and PACRG gene regulatory region with 96 SNPs, with a resolution of 1 SNP per 1 Kb for PARK2 gene regulatory region in a North Indian population, showed an involvement of 11 SNPs in determining the susceptibility towards leprosy. The association was replicated in a geographically distinct and unrelated population from Orissa in eastern India. In vitro reporter assays revealed that the two significantly associated SNPs, located 63.8 kb upstream of PARK2 gene and represented in a single BIN of 8 SNPs, influenced the gene expression. A comparison of BINs between Indian and Vietnamese populations revealed differences in the BIN structures, explaining the heterogeneity and also the reason for non-replication of the associated genomic region in different populations. 相似文献
88.
Mukhopadhyay P Chakraborty S Ponnusamy MP Lakshmanan I Jain M Batra SK 《Biochimica et biophysica acta》2011,1815(2):224-240
Mucins are high molecular weight, multifunctional glycoproteins comprised of two structural classes-the large transmembrane mucins and the gel-forming or secreted mucins. The primary function of mucins is to protect and lubricate the luminal surfaces of epithelium-lined ducts in the human body. Recent studies have identified a differential expression of both membrane bound (MUC1, MUC4 and MUC16) and secreted mucins (MUC2, MUC5AC, MUC5B and MUC6) in breast cancer tissues when compared with the non-neoplastic breast tissues. Functional studies have also uncovered many unique roles of mucins during the progression of breast cancer, which include modulation in proliferative, invasive and metastatic potential of tumor cells. Mucins function through many unique domains that can form complex association with various signaling molecules including growth factor receptors and intercellular adhesion molecules. While there is growing information about mucins in various malignancies including breast cancer, no focused review is there on the expression and functional roles of mucins in breast cancer. In this present review, we have discussed the differential expression and functional roles of mucins in breast cancer. The potential of mucins as diagnostic and prognostic markers and as therapeutic targets in breast cancer have also been discussed. 相似文献
89.
Akhila Chithambharan Lalitha Pottail Rekha Manjunath Mirle Ravimoorthy Rajalakshmi Aruna Ponnusamy 《Indian journal of microbiology》2021,61(3):298
Gold nanoparticles with their excellent biocompatibility are extensively used in pharma and biological applications. Terminalia bellerica (TB) dry fruit parts mediated gold nanoparticles were synthesized using the aqueous extracts. The secondary metabolites screening of the aqueous extracts was done using phytochemical analysis. The green synthesized gold nanoparticles show vibrant colours. They were characterized using UV–Visible spectroscopy, FT-IR spectroscopy, XRD analysis and FE-SEM. The analytical characterization methods ensured the formation of nanoparticles and could predict the nanometric size of the nanoparticles. The study also lay to determine the antibacterial potential of the TB fruit parts and TB fruit parts mediated gold nanoparticles. The pathogens chosen for the study were pathogens from clinical species such as Acinetobacter pneumonia, Bacillus subtilis, and Enterococcus faecalis which cause common infections. The TB fruit part extracts, as well as TB fruit parts mediated gold nanoparticles were capable enough to destroy clinical pathogens.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12088-021-00937-3. 相似文献
90.
Ponnusamy Sasikumar Sivasamy Gomathi Kolandaswamy Anbazhagan Albert Abhishek Eldho Paul Varadaraj Vasudevan Sundaresan Sasikumar Govindan Sadasivam Selvam 《Journal of biomedical science》2014,21(1)