Analysis of MinD mutations reveals residues required for MinE stimulation of the MinD ATPase and residues required for MinC interaction.
The MinD ATPase is critical to the oscillation of the Min proteins, which limits formation of the Z ring to midcell. In the presence of ATP, MinD binds to the membrane and recruits MinC, forming a complex that can destabilize the cytokinetic Z ring. MinE, which is also recruited to the membrane by MinD, displaces MinC and stimulates the MinD ATPase, resulting in the oscillation of the Min proteins. In this study we have investigated the role of lysine 11, present in the deviant Walker A motif of MinD, and the three residues in helix 7 (E146, S148, and D152) that interact electrostatically with lysine 11. Lysine 11 is required for interaction of MinD with the membrane, MinC, MinE, and itself. In contrast, the three residues in helix 7 that interact with lysine 11 are not required for binding to the membrane or activation of MinC. They are also not required for MinE binding; however, they are required for MinE to stimulate the MinD ATPase. Interestingly, the D152A mutant self-interacts, binds to the membrane, and recruits MinC and MinE in the presence of ADP as well as ATP. This mutant provides evidence that dimerization of MinD is sufficient for MinD to bind the membrane and recruit its partners.
Zhou
Huaijin
H
Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
Schulze
Ryan
R
Cox
Sandra
S
Saez
Cristian
C
Hu
Zonglin
Z
Lutkenhaus
Joe
J
D000244:Adenosine Diphosphate / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D019943:Amino Acid Substitution; D018797:Cell Cycle Proteins; D004252:DNA Mutational Analysis; D019281:Dimerization; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D020125:Mutation, Missense; D011485:Protein Binding; D017433:Protein Structure, Secondary
D018797:Cell Cycle Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; C462942:MinC protein, E coli; C093548:MinE protein, E coli; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; C072069:MinD protein, E coli