Interaction of the N-terminal domain of MukB with the bacterial tubulin homologue FtsZ.
The MukB protein is involved in the process of chromosome partition in Escherichia coli and has a domain structure reminiscent of the eukaryotic motor proteins kinesin and myosin. This has led to the suggestion that MukB may function as a motor protein in vivo. In order to test this idea we have recombinantly expressed the N-terminal domain of MukB (residues 1-342) as a poly-His tagged fusion protein for biochemical characterisation. The purified protein (Muk342) is monomeric and has low basal Mg-ATPase (1.23 min(-1)) and Mg-GTPase (0.17 min(-1)) activities. Muk342 binds with high affinity to the prokaryotic tubulin homologue FtsZ and we have evidence that FtsZ can stimulate nucleotide turnover by Muk342. These properties are consistent with MukB functioning as a motor protein using FtsZ as a track or anchor for generating force within E. coli.
Lockhart
A
A
Structural Studies Division, MRC-Laboratory of Molecular Biology, Cambridge, UK. AndrewLockhart/PH/Novartis@PH
Kendrick-Jones
J
J
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone; D003598:Cytoskeletal Proteins; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D020558:GTP Phosphohydrolases / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D017386:Sequence Homology, Amino Acid; D014404:Tubulin / Q000235:genetics
D001426:Bacterial Proteins; D002868:Chromosomal Proteins, Non-Histone; D003598:Cytoskeletal Proteins; D029968:Escherichia coli Proteins; C071525:FtsZ protein, Bacteria; C067035:MukB protein, E coli; D011993:Recombinant Fusion Proteins; D014404:Tubulin; D017301:Ca(2+) Mg(2+)-ATPase; D020558:GTP Phosphohydrolases; C037024:magnesium GTPase