Photo sensing signal transduction
Light is detected by photoreceptors in all domains of life. Surprisingly, photosystems in non-photosynthetic bacteria are mostly undefined. We have identified an entire cascade—light as the input, BphP as the detector, AlgB as the signal transducer, and biofilm formation and virulence factor production as the outputs—enabling crucial insight into light-driven control of bacterial behaviors. Going forward, we will develop P. aeruginosa as a model system for studying photo regulation of physiology of non-photosynthetic bacteria. Specifically, we will characterize the photo-sensing system and its regulon in P. aeruginosa and explore the role of photo sensing in P. aeruginosa-host interactions. In addition, we will test the generality/specificity of our findings in P. aeruginosa by expanding our research to include other bacteria that possess the BphP-AlgB photo-sensing system.
Integration of multiple sensory cues
It is imperative that bacteria decode and integrate varied sensory inputs to make key transitions such as whether to launch a virulence program or remain in a stealth mode to avoid host immune factors. However, how bacteria integrate diverse sensory information is poorly understood. Our goal is to identify the components that connect different signaling pathways. To pursue this goal, we will define how information from photo sensing and quorum sensing is combined, investigate how quorum sensing intersects with other sensory pathways to control biofilm development, and explore the individual and combined roles of photo sensing and quorum sensing in the control of biofilm dispersal.