Intracellular organization & differentiation of bacteria
Dr. Simon Ringgaard
Targeting of cellular components to a particular site in a cell is often a highly regulated process, even in cells as small as bacteria. In bacteria, the proteins regulating as diverse mechanisms as cell division, motility and faithful inheritance of the genome to progeny cells, all require specific and dynamic intracellular localizations that have to be coordinated with the cell cycle. Failure to do so often has detrimental or even lethal consequences. Using the human pathogens Vibrio cholera and Vibrio parahaemolyticus as our model organisms, we study how bacteria control protein localization and establish cellular domains during the cell cycle or in response to environmental changes. In particular, we are interested in understanding how V. parahaemolyticus differentiates from small swimmer cells to large swarmer cells in response to surface contact and how the chemotactic signaling arrays in Vibrio species localize dynamically to the cell poles during the cell cycle. To address these fundamental questions, we use a combination of live cell fluorescence microscopy, genetics, biochemistry and bioinformatics.
Alvarado, A., Kjær, A., Yang, W., Mann, P., Briegel, A., Waldor, M.K., and Ringgaard, S. Coupling chemosensory array formation and localization. Elife. 2017. 6.
Heering, J., Alvarado, A., Ringgaard, S. Induction of Cellular Differentiation and Single Cell Imaging of Vibrio parahaemolyticus Swimmer and Swarmer Cells. J. Vis. Exp. 2017; e55842, 1–8
Heering, J., Ringgaard, S. Differential localization of chemotactic signaling arrays during the lifecycle of Vibrio parahaemolyticus. Front. Microbiol. 2016; 7:1767, doi:10.3389/fmicb.2016.01767
Briegel, A., Ortega, D.R, Mann, P., Kjær, A., Ringgaard, S., Jensen, G.J. Chemotaxis cluster 1 proteins form cytoplasmic arrays in Vibrio cholerae and are stabilized by a double signaling domain receptor DosM. PNAS 2016; 113 (37), 10412-10417, doi:10.1073/pnas.1604693113
Ringgaard, S., Hubbard, T., Mandlik, A., Davis, B.M., Waldor, M.K. RpoS and quorum sensing control expression and polar localization of Vibrio cholerae chemotaxis cluster III proteins in vitro and in vivo. Mol Microbiol 2015 Aug;97(4):660-75. doi: 10.1111/mmi.13053. Epub 2015 Jun 6.
Ringgaard, S., Zepeda-Rivera, M., Xiaoji, W., Schirner, K., Davis, B.M., Waldor, M.K. (2014) ParP prevents dissociation of CheA from chemotactic signaling arrays and tethers them to a polar anchor. Proc Natl Acad Sci U S A. Jan 14;111(2):E255-64