TY - JOUR
T1 - Electron cryomicroscopic visualization of PomA/B stator units of the sodium-driven flagellar motor in liposomes
AU - Yonekura, Koji
AU - Yakushi, Toshiharu
AU - Atsumi, Tatsuo
AU - Maki-Yonekura, Saori
AU - Homma, Michio
AU - Namba, Keiichi
PY - 2006/3/17
Y1 - 2006/3/17
N2 - A motor protein complex of the bacterial flagellum, PomA/B from Vibrio alginolyticus, was reconstituted into liposomes and visualized by electron cryomicroscopy. PomA/B is a sodium channel, composed of two membrane proteins, PomA and PomB, and converts ion flux to the rotation of the flagellar motor. Escherichia coli and Salmonella have a homolog called MotA/B, which utilizes proton instead of sodium ion. PomB and MotB have a peptidoglycan-binding motif in their C-terminal region, and therefore PomA/B and MotA/B are regarded as the stator. Energy filtering electron cryomicroscopy enhanced the image contrast of the proteins reconstituted into liposomes and showed that two extramembrane domains with clearly different sizes stick out of the lipid bilayers on opposite sides. Image analysis combined with gold labeling and deletion of the peptidoglycan-binding motif revealed that the longer one, ∼70 Å long, is likely to correspond to the periplasmic domain, and the other, about half size, to the cytoplasmic domain.
AB - A motor protein complex of the bacterial flagellum, PomA/B from Vibrio alginolyticus, was reconstituted into liposomes and visualized by electron cryomicroscopy. PomA/B is a sodium channel, composed of two membrane proteins, PomA and PomB, and converts ion flux to the rotation of the flagellar motor. Escherichia coli and Salmonella have a homolog called MotA/B, which utilizes proton instead of sodium ion. PomB and MotB have a peptidoglycan-binding motif in their C-terminal region, and therefore PomA/B and MotA/B are regarded as the stator. Energy filtering electron cryomicroscopy enhanced the image contrast of the proteins reconstituted into liposomes and showed that two extramembrane domains with clearly different sizes stick out of the lipid bilayers on opposite sides. Image analysis combined with gold labeling and deletion of the peptidoglycan-binding motif revealed that the longer one, ∼70 Å long, is likely to correspond to the periplasmic domain, and the other, about half size, to the cytoplasmic domain.
KW - Bacterial flagellum
KW - Energy filtering electron cryomicroscopy
KW - Flagellar motor
KW - Liposome
KW - Stator
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U2 - 10.1016/j.jmb.2005.12.041
DO - 10.1016/j.jmb.2005.12.041
M3 - Article
C2 - 16426637
AN - SCOPUS:33644756852
VL - 357
SP - 73
EP - 81
JO - Journal of Molecular Biology
JF - Journal of Molecular Biology
SN - 0022-2836
IS - 1
ER -