Dubey M.,Microbiology and Nanotechnology Research Laboratory |
Bhadauria S.,Microbiology and Nanotechnology Research Laboratory |
Sharma V.K.,National JALMA Institute of Leprosy and other Mycobacterial Diseases ICMR
International Journal of Green Nanotechnology: Biomedicine | Year: 2012
Biosynthesis of nanoparticles by plant extracts is currently under exploration. Biological methods are a good competent to chemical procedures, which are environmentally friendly and convenient. We report the use of new plant extract of Cuscuta reflexa in the extracellular biosynthesis of silver nanoparticles. Bioactive silver nanoparticle synthesis was achieved by reacting the biomass of C. reflexa with aqueous solutions of silver nitrate (AgNO3) at ambient temperature. The formation of silver nanoparticles was confirmed by ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction patterns, and transmission electron microscopy (TEM). In the present study we report the excellent antibacterial activity of silver nanoparticle (with C. reflexa extract) against gram-positive and gramnegative multi-drug-resistant (MDR) bacterial strains using a zone of inhibition method. Scanning electron microscopy (SEM) imaging studies revealed that silver nanoparticles physically damaged the bacterial cell and ultimately led to cell death. © Taylor & Francis Group, LLC.
Desikan P.,Bhopal Memorial Hospital and Research Center |
Chauhan D.S.,National JALMA Institute of Leprosy and Other Mycobacterial Diseases ICMR |
Sharma P.,National JALMA Institute of Leprosy and Other Mycobacterial Diseases ICMR |
Panwalkar N.,Bhopal Memorial Hospital and Research Center |
And 5 more authors.
Indian Journal of Medical Research | Year: 2016
Background & objectives: There is a paucity of data available on genetic biodiversity of Mycobacterium tuberculosis isolates from central India. The present study was carried out on isolates of M. tuberculosis cultured from diagnostic clinical samples of patients from Bhopal, central India, using spoligotyping as a method of molecular typing. Methods: DNA was extracted from 340 isolates of M. tuberculosis from culture, confirmed as M. tuberculosis by molecular and biochemical methods and subjected to spoligotyping. The results were compared with the international SITVIT2 database. Results: Sixty five different spoligo international type (SIT) patterns were observed. A total of 239 (70.3%) isolates could be clustered into 25 SITs. The Central Asian (CAS) and East African Indian (EAI) families were found to be the two major circulating families in this region. SIT26/CAS1_DEL was identified as the most predominant type, followed by SIT11/EAI3_IND and SIT288/CAS2. Forty (11.8%) unique (non-clustered) and 61 (17.9%) orphan isolates were identified in the study. There was no significant association of clustering with clinical and demographic characteristics of patients. Interpretation & conclusions: Well established SITs were found to be predominant in our study. SIT26/CAS1_DEL was the most predominant type. However, the occurrence of a substantial number of orphan isolates may indicate the presence of active spatial and temporal evolutionary dynamics within the isolates of M. tuberculosis. © 2016, Indian Journal of Medical Research. All rights reserved.
Kumar M.,Indian Institute of Integrative Medicine |
Kumar M.,Daiichi Sankyo |
Khan F.G.,Indian Institute of Integrative Medicine |
Sharma S.,Indian Institute of Integrative Medicine |
And 7 more authors.
Microbial Pathogenesis | Year: 2011
The identification of Mycobacterium tuberculosis genes, specifically expressed during infection is a key step in understanding molecular mechanism of mycobacterial pathogenesis. Such genes likely encode proteins required for mycobacterium's survival and progressive infection within the host. In this study, we applied in-vivo-induced antigen technology (IVIAT) to M. tuberculosis and identified 11 putative in-vivo induced genes encoding for immunogenic proteins of diverse functions; these included transcriptional regulators (Rv1460 and Rv2565), biosynthesis and macromolecule metabolism (leuD, guaB1, plcC, hupB and glyS), polyketide synthases (pks6 and pks9), cell processes (ctpA) and one with unknown function (Rv3701c). Quantitative real time-PCR analysis of these genes in the specimens obtained from TB patients demonstrated induced expression of eight genes as compared with bacteria grown in-vitro. In addition, distribution of these genes in different strains of M. tuberculosis was analyzed using PCR and their nucleotide sequence alignments and they were found to be widely distributed among M. tuberculosis isolates including multiple-drug resistant (MDR) and extensively-drug resistant (XDR). This study identified several antigenic determinants of M. tuberculosis expressed during infection, which might help pathogens adapt to or counter hostile environments and suggesting their role during disease process. © 2010 Elsevier Ltd.