The secG deletion mutation of Escherichia coli is suppressed by expression of a novel regulatory gene of Bacillus subtilis

FEBS Letters

Helander, Ilkka M.¹  Kontinen, Vesa P.¹  Tokuda, Hajime¹ 

[1] Laboratory of Vaccine Development, National Public Health Institute, Mannerheimintie 166, FIN-00300 Helsinki, Finland

关键词: Protein translocation;    Cardiolipin;    Helix-turn-helix motif;    SecG;    PgsA;    ScgR;    Bacillus subtilis;   

DOI  :  10.1016/0014-5793(96)00602-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

SecG, a membrane component of E. coli protein translocase, stimulates the translocation of proteins across the cell membrane through the cycle of topology inversion, which is coupled to the membrane-insertion and deinsertion cycle of SecA [Nishiyama et al. (1996) Cell 85, 71–81]. A gene of B. subtilis able to suppress the cold-sensitive phenotype of the secG deletion mutant of E. coli was cloned and found to encode a novel regulatory protein, ScgR. Similarity search revealed homology with known proteins such as GlnR of B. subtilis. Plasmid-encoded ScgR stimulated protein translocation in the deletion mutant. ScgR increased the proportion of cardiolipin at the expense of phosphatidylglycerol, but did not affect the composition of other lipid components of the cell, suggesting that the increased cardiolipin level compensates for the SecG function and thereby stimulates protein translocation.

【 授权许可】

Unknown