MS14-P05 Structural insights into the membrane-anchored model of FtsQ/FtsB/FtsL complex in divisome Yuri Choi (Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul, Korea South) Hyung Ho Lee (Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul, Korea South)email: yuri93@snu.ac.krBacterial cell division is a fundamental process that is initiated by FtsZ protein into a ring structure at midcell and facilitates a set of essential proteins known as the divisome [1,2]. Among them, the FtsQ/FtsB/FtsL complex was known as a scaffold protein connecting upstream and downstream division proteins. Despite previous intensive studies on the FtsQBL complex, the atomic details of the interface between FtsQ and FtsB were not reported yet. To gain an insight into structural organization of the FtsQBL complex, we have determined the crystal structure of periplasmic domain of FtsQ in complex with C-terminal fragment of FtsB and showed that the C-terminal region of FtsB is a key binding region of FtsQ via mutational analysis in vitro and in vivo. Also, we proposed the model of FtsQ/FtsB/FtsL complex in curved membrane, with opposite N-terminal directions of FtsQ and the FtsB/FtsL complex via small-angle X-ray scattering and analytical gel filtration chromatography. These model suggests that the Y-shaped FtsQ/FtsB/FtsL complex might fit well into the curved membrane for membrane anchoring during cytokinesis.References:

[1] Tsang M. J. & Bernhardt, T. G. (2015). Mol. Microbiol. 95, 6.

[2] Trip E. N. & Scheffers, D. (2015). Sci. rep. 5, 18190.
Keywords: Divisome, Cytokinesis, FtsQ