Andrew Cameron

The Cameron lab uses molecular genetics to understand the invisible niches and interactions that link the members of microbial communities. For example, what metabolites are passed between bacterial species in petroleum-contaminated soils, or how does an invasive pathogen sense that it has entered the small intestine? These questions can be answered by studying how bacteria use their genes to adapt to their surroundings.

Our lab uses genomic approaches (RNA sequencing, chromatin immunoprecipitation) to gain broad insight into bacterial lifestyles by studying all genes simultaneously. Then we zoom in to the molecular level and use diverse genetic and biochemical techniques to study protein-DNA and protein-protein interactions at gene promoters.

How bacteria adapt to new environments: One of our goals is to identify ecological features present in the human host that support commensal lifestyles and those features that stimulate pathogenic lifestyles in species such as Escherichia coli and Salmonella enterica. E. coli and S. enterica alternate between life inside and outside of animal hosts, and once inside a host bacteria can be either long-term or transient residents. How then do bacteria sense transitions between regions of the host and between internal and external environments? Once sensed, how are options weighed and genetic programs executed to produce adaptive responses?

Characterizing bacterial communities: Bacteria usually live in complex communities composed of diverse species. We are studying how bacterial species cooperate or compete in contaminated environments as well as in polymicrobial infections. For this we use RNA sequencing and proteomics to identify and quantify genetic and metabolic interactions between different species in microbial ecosystems.

How proteins and DNA control gene expression: We use a combination of in vitro and in vivo techniques to probe how proteins and DNA interact at gene promoters. DNA is usually thought to be a passive carrier of genetic information, but in fact DNA is a dynamic and energetic molecule whose shape changes in response to a variety of factors. Thus, DNA is an active participant in regulating gene expression, and we are particularly interested in how changes to DNA topology and protein structures influence gene expression.