FtsB and FtsL are two essential integral membrane proteins of the bacterial division complex or 'divisome', both characterized by a single transmembrane helix and a juxta-membrane coiled coil domain. The two domains are important for the association of FtsB and FtsL, a key event for their recruitment to the divisome that in turn enables recruitment of the late divisomal components and subsequent completion of the division process. We have previously established that the transmembrane domain of FtsB self-associates in Escherichia coli membranes using a biological assay in vivo. We hypothesized that the FtsB dimer forms a core for the lateral association of FtsL, leading to the the assembly of a higher-order oligomeric FtsB-FtsL complex. Here we present a biophysical analysis performed in vitro that further supports this hypothesis. Using FRET, we have measured the association of fluorophore-labeled transmembrane domains of FtsB and FtsL in both detergent and lipid. Our findings demonstrate that these helices form a very stable higher-order oligomeric complex in isolation. The data also suggest that the transmembrane component is likely to be a major contributor to the stability of the FtsB-FtsL complex.

Transmembrane domains of the bacterial cell division proteins FtsB and FtsL form a stable high-order oligomer: A FRET analysis

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.