A cleavable signal peptide is required for the full function of the polytopic inner membrane protein FliP of Escherichia coli.
FliP is a rare bacterial polytopic membrane protein synthesized with a cleavable highly hydrophobic signal peptide. It is essential for flagellum assembly and for bacterial motility. In this study, we assessed specificity of signal peptide for the FliP function. Like the wild type FliP, two altered FliPs with more hydrophilic Tat- or Sec-dependent signal peptides were both able to restore the motility of the DeltafliP mutant. Therefore, the Tat- and the Sec-dependent signal peptides seemed to be compatible with the FliP function. Moreover, deletion of the FliP signal peptide or replacing it with the transmembrane segment of MotA severely impaired the FliP function. Together these results showed that a cleavable signal peptide is required for the full function of FliP.
Pradel
Nathalie
N
Laboratoire de Chimie Bactérienne, UPR9043, IBSM, CNRS, 31, Chemin Joseph Aiguier, F-13402 Marseille cedex 20, France.
Ye
Changyun
C
Wu
Long-Fei
LF
D002465:Cell Movement / Q000235:genetics / Q000502:physiology; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D005407:Flagella / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins