Bacterial adaptation and differentiation
We use Myxococcus xanthus as a wonderful model system to study bacterial adaptation and differentiation. In particular, we study the signal transduction pathways and networks governing differentiation, motility and the cell cycle. In parallel approaches, we aim to understand how molecular machineries involved in motility and cell division function.
The model organism: Myxococcus xanthus
Cells of Myxococcus xanthus self-organize into two distinct biofilms. In the presence of nutrients, the motile, rod-shaped cells grow and divide, and if present on a solid surface, they form cooperatively feeding colonies in which cells at the edge spread outwards. In response to starvation, growth ceases, cells change their motility behavior and a developmental program is initiated that culminates in the formation of multicellular fruiting bodies. After 24 hrs of starvation, nascent fruiting bodies have formed and the cells that have accumulated inside fruiting bodies differentiate to diploid spores. Thus, fruiting body formation is a wonderful model system to analyze how bacteria coordinate changes in motility behavior, gene expression and cell cycle regulation in response to an environmental stress signal.
The overall goal of our research is to understand how M. xanthus responds to starvation with the formation of spore-filled fruiting bodies. To this end, we study at the molecular and cellular level as well as at the theoretical level
M. xanthus belongs to the myxobacteria that are the only bacteria that cope with starvation with the formation of fruiting bodies. Amazingly, the fruiting bodies formed by different myxobacteria have very different shapes varying from haystack-shaped (as in the case of M. xanthus), stalked, coral-shaped to tree-shaped. We use genome sequencing, comparative genomics and transcriptomics to understand the genetic basis underlying differences in fruiting body morphology as well as the evolution of the genetic program(s) for fruiting body formation.
Finally, in a top-down synthetic (micro)biology approach, we also use the lessons learned from studying naturally occurring bacteria to generate modules for synthetic and streamlined cells
We use a suite of experimental techniques including molecular genetics, biochemistry with protein purification and their in vitro characterization, cell biology with live cell-imaging, proteomics, de novo sequencing of myxobacterial genomes, comparative genomics, and transcriptomics using RNAseq.