Subhadeep Chatterjee
Centre for DNA Fingerprinting and Diagnostics (CDFD), Hyderabad
Subhadeep Chatterjee obtained his M.Sc. degree in Biotechnology from Guru Nanak Dev University, Amritsar in 1998. He completed his Ph.D. in CCMB, Hyderabad. During his Ph.D. work, he identified and characterized two novel virulence functions of an economically important pathogen of rice. In 2005, he joined Prof. Steven E Lindow’s group at the University of California, Berkeley, to pursue a more complex plant– microbe interaction system that also involves an insect vector for transmission of the bacterial pathogen Xylella fastidiosa in several economically important plants like grape, almond, citrus. In his postdoctoral work, he characterized a fatty acid-like extracellular signalling molecule in Xylella fastidiosa. In the applied part of his postdoctoral work, he made transgenic plants that can express the bacterial quorum sensing signalling molecules and were reduced in severity of disease. He also characterized several plant- associated bacteria that can degrade pathogen signalling molecules and, hence, can suppress their virulence in host plants. He was elected Fellow of IASc in 2023.
Session 1E: Lectures by Fellows/Associates
Chairperson: Saraswathi Vishveshwara, IISc, Bengaluru
Understanding the Social Language of Bacteria: Speak or Not to Speak?
Bacteria coordinate their social behaviour in a density-dependent manner by the production of diffusible signal molecules via a process known as quorum sensing (QS). Sensing and adaptation to changing environmental conditions were traditionally attributed to two-component sensors and response regulators. The increasing volume of work now suggests that the coordination of responses to fluctuating environments is very complex, as many microbial species live in communities under natural conditions. We are using the Xanthomonas and Pseudomonas group of plant pathogens which make diverse quorum-sensing signalling molecules to address the mechanism of integration and adaptation to changing environmental conditions. Our work has shown that fine-tuning of QS regulatory circuits in closely related members of the Xanthomonas group of phytopathogens contributes to their lifestyle change inside the host. We are also trying to understand how QS-mediated social structure and individuality in the bacteria coexist to improve their fitness in fluctuating environments. Our interest is also in understanding the mechanism by which bacterial pathogens could integrate cell density signalling, host response and environmental signal to coordinate virulence and regulation of gene expression. Speaker’s Profile