Inhibition of FtsZ polymerization by SulA, an inhibitor of septation in Escherichia coli
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS 66160
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Communicated by Richard M. Losick, Harvard University, Cambridge, MA (received for review August 28, 1997)
Abstract
The bacterial cell division protein FtsZ assembles into the cytokinetic Z ring that directs cytokinesis in prokaryotes. In Escherichia coli the formation of the Z ring is prevented by induction of the cell division inhibitor SulA (SfiA), a component of the SOS response. Here we show that a MalE-SulA fusion that retains this inhibitory function in vivo inhibits the GTPase activity and polymerization of FtsZ in vitro. MalE-SulA10, which does not block Z ring formation in vivo, is unable to inhibit the GTPase activity and polymerization in vitro. Furthermore, FtsZ114, which is refractory to SulA in vivo, is not inhibited by MalE-SulA. These results indicate that SulA blocks Z ring formation by blocking FtsZ polymerization.
Footnotes
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↵ * To whom reprint requests should be addressed. e-mail: jlutkenh{at}kumc.edu.
- Copyright © 1998, The National Academy of Sciences
