Analysis of the FliM/FliG motor protein interaction by two-hybrid mutation suppression analysis.
The Escherichia coli motor proteins FliM and FliG physically interact, presumably to control one or more of the functions of the bacterial flagellum clockwise/counterclockwise (CW/CCW) switch. We have previously demonstrated this interaction using the yeast two-hybrid system and have identified mutations in fliG that disrupt the interaction. Starting with the most interaction-defective of these fliG mutants, we mutagenized fliM to identify suppressor mutations that restore the FliM/FliG two-hybrid interaction. Certain fliM suppressor mutations exhibit allele specificity. These mutations help define a FliG-interaction surface on FliM. Moreover, the pattern of suppression suggests that two distinct sites on FliG interact with FliM, perhaps with two FliM molecules in a dimer per molecule of FliG.
Passmore
Steven E
SE
Department of Biological Sciences, California State University, Long Beach, Long Beach, CA 90840, USA.
Meas
Rithy
R
Department of Biological Sciences, California State University, Long Beach, Long Beach, CA 90840, USA.
Marykwas
Donna L
DL
Department of Biological Sciences, California State University, Long Beach, Long Beach, CA 90840, USA.
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology*; D008954:Models, Biological; D008958:Models, Molecular; D016296:Mutagenesis; D025941:Protein Interaction Mapping; D013489:Suppression, Genetic; D020798:Two-Hybrid System Techniques
D001426:Bacterial Proteins; C075660:Flig protein, Bacteria; C066821:FliM protein, Bacteria