However, there is no information yet on the function of bacterial dynamin-like proteins in vivo. A possible function in cell division has been proposed [13]. FtsZ is a tubulin ortholog that initiates cytokinesis

by forming a ring structure at the cell centre. FtsZ recruits further proteins that eventually lead to the formation of a septum between the separated sister chromosomes [14, 15]. In E. coli, proteins are assembled in a rather linear pathway [16], while in B. subtilis, a time delay exists between early recruited proteins (such as FtsA and ZapA) and late check details division proteins (such as FtsL and DivIb), indicating that proteins are recruited as complexes rather than singly [17]. Late division proteins include penicillin-binding proteins (Pbps) that synthesize the cell wall between

the daughter cells. For growth as rods, actin-like MreB proteins are essential in many bacteria, interacting with Pbps and other membrane proteins involved in cell wall synthesis [18, 19]. According to one theory, MreB forms filamentous structures underneath the cell membrane that direct the incorporation of new cell wall material via an interaction with the synthetic enzymes. The depletion of MreB leads to the generation of round cells that eventually lyse [20], showing that the protein plays an important function in cell shape maintenance. Eukaryotic and prokaryotic membranes contain an asymmetric distribution of lipids. Especially cholesterol and sphingolipids in eukaroytes cluster into so called lipid rafts [21]. These dynamic microdomains also cluster proteins, many of which are involved in the transport RGFP966 of membrane components Dapagliflozin and in signal transduction. Flotillins are a class of membrane proteins that are PLX-4720 associated with lipid rafts [22, 23], but their detailed function is unclear. Flotillins are characterized by the SPFH domain of unknown function and extended heptad repeat regions. Recently, flotillin-like proteins FloT and YqfA have been implicated in the clustering of a signal transduction protein in the membrane of B. subtilis cells [24], revealing yet another striking parallel

between pro – and eukaryotic cells. In our work, we show that B. subtilis dynamin ortholog (termed DynA) plays a role in cell division. DynA and flotillin-like protein FloT synergistically affect cell division and cell morphology, suggesting that lipid raft formation and dynamin-driven membrane modification are important for cytokinesis and cell shape maintenance in bacteria. Results DynA plays a role in cell division We deleted the dynA (ypbR) gene by long flanking sequence homology PCR, such that only the first and last 100 bp of the gene remained within the chromosome, disrupted by a tet cassette. We also generated a truncated version of dynA through the insertion of a plasmid into the dynA gene, driving the downstream gene with a xylose-inducible promoter.