Subunit a of proton ATPase F0 sector is a substrate of the FtsH protease in Escherichia coli

FEBS Lett. 1996 Dec 9;399(1-2):26-8. doi: 10.1016/s0014-5793(96)01283-5.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Dependent Proteases
  • Bacterial Proteins / metabolism*
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins
  • Hydrolysis
  • Membrane Proteins / metabolism*
  • Proton-Translocating ATPases / chemistry
  • Proton-Translocating ATPases / metabolism*
  • Substrate Specificity


  • Bacterial Proteins
  • Escherichia coli Proteins
  • Membrane Proteins
  • ATP-Dependent Proteases
  • FtsH protein, E coli
  • Proton-Translocating ATPases