Depletion of SecDF-YajC causes a decrease in the level of SecG: implication for their functional interaction.

Yoshihisa Kato; Ken-ichi Nishiyama; Hajime Tokuda

doi:10.1016/s0014-5793(03)00847-0

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Depletion of SecDF-YajC causes a decrease in the level of SecG: implication for their functional interaction.

Yoshihisa Kato·Ken-ichi Nishiyama·Hajime Tokuda

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Abstract

SecA and an apparatus comprising SecYEG and SecDF-YajC complexes catalyze protein translocation across the Escherichia coli membrane. SecDF-YajC and SecG facilitate membrane insertion of SecA, which is the driving force for protein translocation. Here we report that SecDF-YajC depletion together with SecG depletion nearly completely inhibits protein translocation both in vivo and in vitro, although SecDF-YajC had been thought to be unnecessary for in vitro translocation. The level of SecG in membranes decreased to about half upon SecDF-YajC depletion and recovered to a normal level when SecDF-YajC was expressed. SecDF-YajC inhibited disulfide bond formation between two SecG molecules possessing a single cysteine residue. These results suggest functional interaction between SecDF-YajC and SecG.

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Antigens, Bacterial Bacterial Proteins Dimerization Escherichia coli Escherichia coli Proteins Gene Expression Regulation, Bacterial Membrane Proteins Membrane Transport Proteins Mutation Protein Transport SEC Translocation Channels Transport Vesicles Journal Article Research Support, Non-U.S. Gov't

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Yoshihisa Kato, Ken-ichi Nishiyama, Hajime Tokuda. 2003-08-28. Depletion of SecDF-YajC causes a decrease in the level of SecG: implication for their functional interaction.. https://doi.org/10.1016/s0014-5793(03)00847-0

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