Bacterial pathogens survive in complex host environments in which they encounter commensal microbial communities and host immune molecules. They engage in interactions with the resident microbiota and host immune effectors during infection. These inter-bacterial and host-pathogen interactions have significant impact on the colonization of pathogens and bacterial disease pathogenesis. We are interested in understanding the molecular details and consequences of these interactions in disease pathogenesis. We employ a wide range of tools including microbiology, biochemistry, structural biology, and animal infection studies to elucidate the molecular mechanisms of bacterial pathogenesis. We are also interested in extending our basic research findings into translational studies to identify novel therapeutic and prophylactic interference strategies to treat or prevent bacterial infections. Two major areas of focus include: role of bacterial intercellular communication in virulence, and role of bacterial adaptive responses to metal limitation in host-pathogen interactions and bacterial pathogenesis.