Indranil Biswas, Ph.D.
Microbiology, Molecular Genetics and Immunology
Ph.D., University of Paris VII, Paris, France
Postdoctoral Fellow, NIDDK/NIH & Emory University
Publications: Click here
Gram-positive pathogens like Streptococci are the leading causes of human infections. These bacteria can cause diverse array of diseases such as pneumonia, meningitis, endocarditis, necrotizing faciitis to name a few. During the last two decades, gram-positive bacteria are becoming increasingly resistant to the available drugs, a very serious concern. These bacteria express a wide range of virulence factors that enable them to establish infections. Most of these virulence factors are either secreted or cell-wall associated. Several proteases play an important role in the expression, processing and maturation of these virulence factors. One of the main focuses of our laboratory is to study how various surface proteases affect virulence factor expression in streptococci. We are also studying how these proteases affect biofilm formation by various streptococci such as S. mutans.
A second project of the laboratory is to study the regulation of virulence gene expression in streptococci such as S. pyogenes and S. mutans. Expression of virulence factors is under complex regulatory networks and is not fully understood in streptococci. Our laboratory is interested in the mechanisms by which these bacteria regulate its virulence repertoire in response to host signals encountered during infection. Specifically, we have focused our studies on the molecular mechanisms of two-component signal transduction pathways that regulate a wide range of virulence genes in various streptococci. Our long term goal is to increase overall knowledge of gram-positive bacterial pathogenesis and to develop new treatment strategies.
Recently our lab started research on Acinectobacter baumannii, an emerging nosocomial pathogen involved in a variety of infections ranging from minor soft-tissue infections to more severe infections such as ventilator-associated pneumonia and bacteremia. A. baumannii has the ability to acquire an antibiotic resistance cassette from the environment and this trait has allowed the organism to persist in healthcare settings and also has the remarkable ability to survive prolonged periods under highly desiccated conditions on dry surfaces, a phenomenon that is not commonly found with other Gram-negative pathogens. The primary goals of the lab are to study the mechanisms of desiccation tolerance, develop genetic tools to study virulence and discover novel anti-infectives.
Selected Recent Publications
Biswas I, Mettlach J. Targeted Gene Replacement in Acinetobacter baumannii. Methods Mol Biol. 2019; 1946: 95-106. doi: 10.1007/978-1-4939-9118-1_10.
Biswas S, Keightley A, Biswas I. Mol Oral Microbiol. Characterization of a stress tolerance-defective mutant of Lactobacillus rhamnosus LRB. 2019 Aug; 34 (4):153-167. doi: 10.1111/omi.12262. Epub 2019 Jun 7. PMID: 31056830
Shankar M, Hossain MS, Biswas I. Pleiotropic Regulation of Virulence Genes in Streptococcus mutans by the Conserved Small Protein SprV. J Bacteriol. 2017 Mar 28;199(8). pii: e00847-16. doi: 10.1128/JB.00847-16. PMID: 28167518
Jana B, Tao L, Biswas I. Strain-Dependent Recognition of a Unique Degradation Motif by ClpXP in Streptococcus mutans. mSphere. 2016 Dec 7;1(6). pii: e00287-16. PMID: 27981232
Vijayakumar S, Rajenderan S, Laishram S, Anandan S, Balaji V, Biswas I. Biofilm Formation and Motility Depend on the Nature of the Acinetobacter baumannii Clinical Isolates. Front Public Health. 2016 May 24; 4: 105. doi: 10.3389/fpubh.2016.00105. PMID: 27252939
Biswas S, Cao L, Kim A, Biswas I. SepM, a Streptococcal Protease Involved in Quorum Sensing, Displays Strict Substrate Specificity. J Bacteriol. 2015 Nov 9;198(3):436-47. doi: 10.1128/JB.00708-15. PMID: 26553848
Biswas I. Genetic tools for manipulating Acinetobacter baumannii genome: an overview. J Med Microbiol. 2015 May 6. doi: 10.1099/jmm.0.000081.
20th International Conference on Bacilli and Gram-Positive Bacteria (Maryland, USA): Additional references