Assembly of motor proteins, PomA and PomB, in the Na+-driven stator of the flagellar motor.
PomA and PomB are transmembrane proteins that form the stator complex in the sodium-driven flagellar motor of Vibrio alginolyticus and are believed to surround the rotor part of the flagellar motor. We constructed and observed green fluorescent protein (GFP) fusions of the stator proteins PomA and PomB in living cells to clarify how stator proteins are assembled and installed into the flagellar motor. We were able to demonstrate that GFP-PomA and GFP-PomB localized to a cell pole dependent on the presence of the polar flagellum. Localization of the GFP-fused stator proteins required their partner subunit, PomA or PomB, and the C-terminal domain of PomB, which has a peptidoglycan-binding motif. Each of the GFP-fused stator proteins was co-isolated with its partner subunit from detergent-solubilized membrane. From these lines of evidence, we have demonstrated that the stator proteins are incorporated into the flagellar motor as a PomA/PomB complex and are fixed to the cell wall via the C-terminal domain of PomB.
Fukuoka
Hajime
H
Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-Ku, Nagoya 464-8602, Japan.
Yakushi
Toshiharu
T
Kusumoto
Akiko
A
Homma
Michio
M
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D005407:Flagella / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020409:Molecular Motor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009068:Movement / Q000502:physiology; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D015222:Sodium Channels / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism; D044149:Vibrio alginolyticus / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D020409:Molecular Motor Proteins; C107540:PomA protein, Vibrio; C107541:PomB protein, Vibrio; D011993:Recombinant Fusion Proteins; D015222:Sodium Channels; D049452:Green Fluorescent Proteins; D012964:Sodium