Abstract 9458197 Bacterial cytokinesis will be analyzed with genetic, biochemical and molecular approaches. It has been shown that the control of the placement of the division septum in Escherichia coli is regulated by a 3 gene operon and one of the genes products provides topological specificity. It has also been shown that an essential septation protein, FtsZ is important to cytokinesis. It forms a membrane-associated ring structure at the site of septum formation. This ring shrinks as it remains associated with the leading edge of the ingrowing septum until cytokinesis is complete. In vitro, the protein self-associates into filamentous structures upon binding of GTP. We will develop a quantitative assay for FtsZ polymerization and study the role of nucleotide hydrolysis in Fts-multimerization. Genetic studies have suggested that FtsZ interacts with a number of other division related proteins. Several of these will be tested in purified systems by a variety of methods. In addition, peptide- tagged derivatives of FtsZ will be used in an unbiased search for proteins that interact directly with FtsZ. %%% Although much is known about the genetics and physiology of the bacterium, Escherichia coli, much less is known about mechanisms involved with converting one cell into two cells. This work should deepen our understanding of the genetic regulation of and the physiological mechanisms involved in cell division. ***
