Spore formation in the Gram negative bacterium, Myxococcus xanthus

• Applicant: Dr. Chris van der Does, since 7/2013
• Subject Area: Metabolism, Biochemistry and Genetics of Microorganisms
• Term: from 2013 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 234081228

The ability to withstand periods of environmental stress by differentiation into environmentally resistant, metabolically quiescent resting stages (often termed spores or cysts) is phylogenetically widespread amongst bacteria. However, this differentiation mechanism is only well understood in the case of Gram positive endospore formation in which the spore is matured within a mother cell. Myxococcus xanthus is a Gram negative bacterium which differentiates into heat-resistant, metabolically quiescent spores to survive periods of nutrient limitation. Unlike endospore formation, M. xanthus sporulation involves rearrangement of the entire rod-shaped vegetative cell into a spherical spore in the absence of a septation/cell division event. M. xanthus spores lack peptidoglycan (cell wall) and are surrounded by a rigid, carbohydrate-rich spore coat. In our working hypothesis, peptidoglycan is first rearranged and then degraded in a process that is coordinated with assembly of a rigid spore coat. We will identify and characterize proteins involved in rearrangement and degradation of the peptidoglycan. Additionally, we have previously identified two protein systems, termed Exo and Nfs, necessary for export of spore coat polysaccharides and assembly of the compact spore coat, respectively. We will apply a combination of genetic, biochemical, and cell biology approaches to characterize the function of these proteins. These lines of research promise to unravel novel mechanisms involved in core bacterial physiological process such as cell wall remodeling and assembly of surface structures.

• DFG Programme: Research Grants
• Ehemalige Antragstellerin: Dr. Penelope Higgs, until 7/2013