1. Early in my career, we had purified for the first time the outer membrane protein OmpU and showed it to be a porin and deciphered its role in Vibrio cholerae virulence (Journal of Bacteriology, 1996). Since then, many labs in the world have used our method of purification and lot of studies has been done fetching more than 70 citations so far.



2. In and around the year 2000, my laboratory took the challenge of studying the gene expression by growing V. cholerae inside host. We first showed how to isolate pure V. cholerae from rabbit ileal loop. My lab was the first in India and abroad to study in vivo gene expression in V. cholerae by two simple approaches; we were the first to adopt differential display in prokaryotes and developed macroarray using a cosmid library constructed in our laboratory. This was done in an age when microarray technology was not there. With these strategies my laboratory has identified a number of in-vivo induced genes in V. cholerae and deciphered their role in pathogenesis as well as survival of the organism (Infection & Immunity, 2000; FEMS Microbiology letters 2000; FEBS Letters 2002; Biochem Biphys Res Commun 2002, 2005). 



3. Through in-silico studies my laboratory discovered a block of genes in V. cholerae genome and proposed their role in pathogenicity/secretion (In silico Biology, 2003). Immediately one prime group working in V. cholerae under the leadership of John Mekalanos, Prof.  & Chair, Harvard Medical School, USA proved the hypothesis in wet lab and acknowledged my contributions in his first PNAS and subsequent publications in Science and other high impact journals and also verbally when I met him at Calcutta. This publication has more than 66 citations till date.



4. A new algorithm has been developed for identification of genomic islands in prokaryotes in collaboration with ISI, Kolkata. Using this algorithm, my laboratory discovered a novel RTX-like toxin in V. cholerae (BMC Genomics 2007, FEMS Microbiology Letters 2008).



5. We have delineated the entire signal transduction pathway in intestinal epithelial cells following V. cholerae infection leading to inflammatory reactions and demonstrated that V. cholerae flagellin specifically activates TLR5 leading to pro-inflammatory cytokine production (microbes & Infection 2004; FEBS Letters 2005, Int J Biochem Cell Biol 2007, FEBS Journal 2007, Microbial Pathogenesis 2008, Can J Microbiol 2009, Innate Immunity 2009, Molecular Immunology 2009).



6. My laboratory for the first time showed that aqueous garlic extract chelates As3+ and inhibit arsenic induced toxicity both in-vitro & in-vivo systems (Food & Chemical Toxicology 2008). This study has a great societal impact which has been discussed in various popular Science journals and newspapers, websites such as New Scientist, Nature India, Iran daily, The telegraph-Kolkata, Wikipedia, yahoo news and so on.



7. We have developed, in collaboration with IIT-KGP, a novel ANN-based computer aided technique which could distinguish the early and advanced stages of Oral Submucous Fibrosis, a precancerous condition of the oral cavity (Journal of Clinical Pathology 2005, Oral Oncology 2006, Tissue & Cell 2008; Journal of Biological Systems 2010). This study was covered by The Statesman, Kolkata.



8. I participated in a Mega project which, under the able leadership of Prof. SK Brahmachari, created the largest DNA variation database of the people of India and is a useful resource for construction of drug response/disease predisposition maps and future risk management.



9. Our study has shown zinc depletion in tissues of patients suffering from the precancerous oral submucous fibrosis. Based on this and in collaboration with the doctors at Dr. R Ahmed Dental College & Hospital, Kolkata, we found that zinc and vitamin A supplementation along with cessation of oral habit could be an effective treatment modality for this disease (Biological Trace Elements Research 2002, BMJ Case Report 2010).



10. Our group has recently discovered a novel mechanism of transportation of cholera toxin via outer membrane vesicles into the host (FEBS Letters 2011). The comment from the reviewer stated “This is an unexpected and potentially important discovery for cholera research and therapy”.

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11. Very recently our laboratory has developed for the first time in India and abroad a co-culture model to study the interaction of V. cholerae and host. We have developed epithelial cell-dendritic cell co-culture that is technologically challenging. With this co-culture model, we have demonstrated for the first time the role of TSLP and other mediators released from epithelial cells in response to V. cholerae colonization in actively influencing dendritic cells to initiate inflammatory response. Here also V. cholerae flagellin was involved in initiating the inflammatory response (Int J Biochem Cell Biol 2012).



12. We have demonstrated for the first time that V. cholerae O395 OMVs modulate the epithelial pro-inflammatory response and activate dendritic cells which promoted the T cells polarization towards an inflammatory Th2/Th17 response (J Biol Chem 2013).