Universität zu Köln 

Prof. Dr. Marc Bramkamp

since 1.04.2012: LMU München, Department Biologie I, Bereich Mikrobiologie
email: marc.bramkamp@lmu.de
phone: +49 (0)89 2180-74611
website

until 31.03.2013: Institut für Biochemie, Universität Köln

Bacterial cell biology is an intense field of research. However, the lateral organisation of the bacterial cell membrane has not been analysed in detail and the influence on cellular processes such as cytokinesis and development remains largely unknown. We have already identified a bacterial flotillin that resides in membrane microdomains and may contribute to lateral membrane organisation. Flotillins are raft marker proteins which are extensively modified on posttranslational level. These proteins assemble into oligomeric complexes which likely regulates their function. Within the next funding period we will analyse the function of bacterial flotillin homologues in Bacillus subtilis (YuaG, YqfA). YuaG seems to provide a scaffold for signalling kinases that are involved in sporulation and biofilm formation of Bacillus subtilis. We could further show that YuaG is part of lipid microdomains and associates tightly with negatively charged phospholipids (such as cardiolipin). In addition we have identified a bacterial dynamin-like protein which exhibits a synthetic sick phenotype with YuaG. DynA is involved in membrane tethering and fusion. DynA localises to septa and may contribute to efficient septum closure. DynA self-organises into dynamic protein assemblies on membrane surfaces, thereby leading to membrane fusion. This process does not need GTP hydrolysis. In the next funding period we will study how DynA mediates membrane fusion by ordered complex formation and how this complex is disassembled after membrane fusion. DynA is an unusual example of posttranslational control by protein assembly, because nucleotide hydrolysis and mechanical work seem to be separated. This is in striking contrast to other proteins of the dynamin superfamily.

Running time: 2011 – 2013

Recent publications:

Bach, J.N, Bramkamp, M. (2013). Flotillins functionally organize the bacterial membrane. Mol Microbiol. 88, 1205-1217. doi: 10.1111/mmi.12252.

Bramkamp, M. (2012). Structure and function of bacterial dynamin-like proteins. Biol. Chemistry., doi: 10.1515/bc-2012-0185, in press. Review

Bürmann, F., Sawant, P. and Bramkamp, M. (2012). Identification of interaction partners of the dynamin-like protein DynA from Bacillus subtilis. Commun Integr Biol., 5. doi.org/10.4161/cib.20215

Bürmann F., Ebert, N., van Baarle, S., and Bramkamp, M. (2011). A bacterial dynamin-like protein mediating nucleotide independent membrane fusion. Mol. Microbiol. 79, 1294-304.

Donovan, C., Schwaiger, A., Krämer, R., and Bramkamp, M. (2010). Subcellular localization and characterization of the ParAB system from Corynebacterium glutamicum. J. Bacteriol. 192, 3441-3451.

van Baarle, S. and Bramkamp, M. (2010). The MinCDJ system in Bacillus subtilis prevents minicell formation by promoting divisome disassembly. PLoS One 5, e9850.

Wadenpohl, I. and Bramkamp, M. (2010). DivIC stabilizes FtsL against RasP cleavage. J. Bacteriol. 192, 5260-5263.

Wadenpohl, I. and Bramkamp, M. (2010). Fluoreszierende Proteine als Werkzeuge in der Mikrobiologie. BIOspektrum 1/2010, 51-53. (invited review).

Donovan, C. and Bramkamp, M. (2009). Characterization and subcellular localisation of a bacterial flotillin homologue. Microbiology 155, 1786-1799.