A conserved cell division protein directly regulates FtsZ dynamics in filamentous and unicellular actinobacteria
FtsZ, Mycobacterium smegmatis, Streptomyces venezuelae, cell division, infectious disease, microbiology, prokaryotic development, sporulation
Bacterial cell division is driven by the polymerization of the GTPase FtsZ into a contractile structure, the so-called Z-ring. This essential process involves proteins that modulate FtsZ dynamics and hence the overall Z-ring architecture. Actinobacteria like and lack known key FtsZ-regulators. Here we report the identification of SepH, a conserved actinobacterial protein that directly regulates FtsZ dynamics. We show that SepH is crucially involved in cell division in and that it binds FtsZ via a conserved helix-turn-helix motif, stimulating the assembly of FtsZ protofilaments. Comparative studies using the SepH homolog from further reveal that SepH can also bundle FtsZ protofilaments, indicating an additional Z-ring stabilizing function . We propose that SepH plays a crucial role at the onset of cytokinesis in actinobacteria by promoting the assembly of FtsZ filaments into division-competent Z-rings that can go on to mediate septum synthesis.
Ramos-León, F., Bush, M. J., Sallmen, J. W., Chandra, G., Richardson, J., Findlay, K. C., McCormick, J. R., & Schlimpert, S. (2021). A conserved cell division protein directly regulates FtsZ dynamics in filamentous and unicellular actinobacteria. eLife, 10. https://doi.org/10.7554/eLife.63387