Microbial Inter-Species Interactions

Bacteria utilize numerous sensing and signaling molecules to identify their host and coordinate changes in gene expression that allows for infection, as well as to sense the presence of other bacteria within the environment. Signals discovered to date include small molecules or proteins that are secreted from the host and bacterial quorum sensing molecules that indicate adequate cell density for infection.

Environmental signals are also used by bacteria to identify conditions when the host defenses are weakened, potentially signaling entry into an appropriate host for infection, and to identify a niche for colonization. Our work on globin coupled sensor signaling identified a protein within the plant pathogen Pectobacterium carotovorum ssp. carotovorum WPP14 , termed PccGCS, that affects oxygen-dependent rotting of a potato host. These studies also identified changes in virulence factor excretion and motility, as well as protein-protein interactions and changes in gene expression, that suggested widespread effects of PccGCS signaling. 

Building on this work, our current studies are focused on understanding how oxygen-dependent PccGCS signaling within P. carotovorum intersects with bacterial quorum sensing and plant defense pathways, as well as bacterial inter-species competition. 

 

Papers on this project:

Burns, J.L.; Jariwala, P.B.; Rivera, S.; Fontaine, B.M.; Briggs, L.; Weinert, E.E. (2017) Oxygen-Dependent Globin Coupled Sensor Signaling Modulates Motility and Virulence of the Plant Pathogen Pectobacterium carotovorum. ACS Chem. Biol. 12, 2070-2077. DOI: 10.1021/acschembio.7b00380