Subunit a of proton ATPase F0 sector is a substrate of the FtsH protease in Escherichia coli.
Escherichia coli FtsH is a membrane-bound ATPase with a proteolytic activity against the SecY subunit of protein translocase. We now report that subunit a of the membrane-embedded Fo part of H+-ATPase is another substrate of FtsH. Pulse-chase experiments showed that subunit a is unstable when it alone (without Fo subunits b and c) was oversynthesized and that it is stabilized in the ftsH mutants. Selective and ATP-dependent degradation of subunit a by purified FtsH protein was demonstrated in vitro. These results suggest that FtsH serves as a quality-control mechanism to avoid potentially harmful accumulation of free subunit a in the membrane.
Akiyama
Y
Y
Department of Cell Biology, Institute for Virus Research, Kyoto University, Japan.
Kihara
A
A
Ito
K
K
D049069:ATP-Dependent Proteases; D001426:Bacterial Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006868:Hydrolysis; D008565:Membrane Proteins / Q000378:metabolism*; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000378:metabolism*; D013379:Substrate Specificity
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D049069:ATP-Dependent Proteases; C513383:FtsH protein, E coli; D006180:Proton-Translocating ATPases