Bacteria spend a great deal of time in their native environments growing in association with exogenous surfaces. Cells in these attached communities exist in a physiological state that is distinct from the planktonic lifestyle traditionally attributed to bacteria. A desire to understand how bacteria achieve the surface-adapted state unifies the various research topics in our group.
Flagellar motility and chemotaxis
Bacteria use sophisticated machines called flagella to swim toward preferred niches. Flagellar motility has a multi-faceted effect on surface colonization: it allows bacteria to locate desired niches, to interact favorably with surfaces and to recognize contact with other objects. By focusing specifically on the flagellum’s role in mechanosensing, we have discovered a set of signaling pathways that links flagellar motility to adhesion in the model organism Caulobacter crescentus. Functionally characterizing components of these pathways using genetic, cell biological and structural approaches allows us to shed light on an overlooked role for the flagellum in signal transduction.
Circuitry of signal transduction networks
Biological organisms process massive amounts of sensory information to coordinate behavior with their surroundings. Chemical, physical, developmental and social cues are some of the many factors that influence whether or not a bacterial cell commits to surface colonization. Parsing how the sensory transduction pathways for these diverse stimuli converge presents an ideal system to interrogate the logic of decision making. We combine genome-wide phenotyping, behavioral tracking and traditional genetic approaches to model signaling networks that integrate environmental stimuli to control behavior.
Synthesis of complex polysaccharides
Bacteria decorate their cell surfaces with sophisticated polysaccharides. These glycans form intimate contacts with objects in the environment, and they are critical colonization factors. We use genetics, enzymology and chemistry to characterize the machinery that assembles complex polysaccharides. We are also deploying knowledge of how these compounds are synthesized to produce new polysaccharide-based materials. Combining discovery of novel glycans with synthetic biology allows us to design polysaccharides with high chemical precision for a variety of medical, industrial and agricultural applications.
The interests described above are by no means exhaustive. We guide trainees to develop projects that both satisfy their scientific curiosity and advance their career aspirations. Prospective members have the option to infuse their own ideas into current topics in the lab or to propose entirely new directions.