title: Dr-FtsA, an actin homologue in Deinococcus radiodurans differentially affects Dr-FtsZ and Ec-FtsZ functions in vitro.
abstract: The Deinococcus radiodurans genome encodes homologues of divisome proteins including FtsZ and FtsA. FtsZ of this bacterium (Dr-FtsZ) has been recently characterized. In this paper, we study FtsA of D. radiodurans (Dr-FtsA) and its involvement in regulation of FtsZ function. Recombinant Dr-FtsA showed neither ATPase nor GTPase activity and its polymerization was ATP dependent. Interestingly, we observed that Dr-FtsA, when compared with E. coli FtsA (Ec-FtsA), has lower affinity for both Dr-FtsZ and Ec-FtsZ. Also, Dr-FtsA showed differential effects on GTPase activity and sedimentation characteristics of Dr-FtsZ and Ec-FtsZ. For instance, Dr-FtsA stimulated GTPase activity of Dr-FtsZ while GTPase activity of Ec-FtsZ was reduced in the presence of Dr-FtsA. Stimulation of GTPase activity of Dr-FtsZ by Dr-FtsA resulted in depolymerization of Dr-FtsZ. Dr-FtsA effects on GTPase activity and polymerization/depolymerisation characteristics of Dr-FtsZ did not change significantly in the presence of ATP. Recombinant E. coli expressing Dr-FtsA showed cell division inhibition in spite of in trans expression of Dr-FtsZ in these cells. These results suggested that Dr-FtsA, although it lacks ATPase activity, is still functional and differentially affects Dr-FtsZ and Ec-FtsZ function in vitro.
authors.affiliation: Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400 085, India.
authors.forename: Kruti
authors.initials: K
authors.lastname: Modi
authors.affiliation: Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400 085, India.
authors.forename: Hari S
authors.initials: HS
authors.lastname: Misra
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000378:metabolism*; D002455:Cell Division / Q000235:genetics; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D034301:Deinococcus / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D020558:GTP Phosphohydrolases / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D001426:Bacterial Proteins; D003598:Cytoskeletal Proteins; C065103:FtsA protein, Bacteria; C071525:FtsZ protein, Bacteria; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D020558:GTP Phosphohydrolases