Research focus: 

The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-CRISPR-associated (Cas) system bestows adaptive immunity to bacteria against invading mobile genetic elements (MGE). It captures proto-spacers from invading MGEs and incorporates them in the CRISPR array with the help of Cas proteins. The system has also been implicated in alternative functions like governing virulence and bacterial physiology. In some bacterial species, including Salmonella, a few selective proto-spacers have been found within the bacterial genome, thereby supporting the role of the CRISPR-Cas system in endogenous gene regulation. Salmonella possesses a type I-E CRISPR-Cas system comprising two CRISPR arrays, CRISPR-I and CRISPR-II, and one cas operon. We traced the spacer targets (majorly showing partial complementarity) onto the Salmonella genome. Our lab focuses on understanding how the endogenous CRISPR-Cas system regulates different biofilm phenotypes of Salmonella enterica subspecies enterica. Research in our lab demonstrated that the CRISPR-Cas system differentially regulated surface-attached and pellicle biofilm formation by modulating the expression of biofilm-associated genes. Further, through computational analysis of this system we have revealed an interesting evolutionary pattern of this system in the serovars of Salmonella enterica subspecies enterica. We are trying to understand the molecular mechanisms of CRISPR-mediated regulation of bacterial physiology.