Characterization of the type III export signal of the flagellar hook scaffolding protein FlgD of Escherichia coli.
Transport of flagellar structural proteins beyond the cytoplasmic membrane is accomplished by a type III secretory pathway [flagellar type III secretion system (fTTSS)]. The mechanism of substrate recognition by the fTTSS is still enigmatic. Using the hook scaffolding protein FlgD of Escherichia coli as a model substrate, it is demonstrated that the export signal is contained within the N-terminal 71 amino acids of FlgD. Analysis of frame-shift mutations and alterations of the nucleotide sequence suggest a proteinaceous nature of the signal. Furthermore, the physicochemical properties of the first about eight amino acids are crucial for export.
Weber-Sparenberg
Corinna
C
Fachbereich Biologie/Chemie, Abteilung Mikrobiologie, Universität Osnabrück, Barbarastrasse 11, 49069 Osnabrück, Germany.
Pöplau
Petra
P
Brookman
Heiner
H
Rochón
Maike
M
Möckel
Carolin
C
Nietschke
Monika
M
Jung
Heinrich
H
D000469:Alkaline Phosphatase / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005407:Flagella / Q000378:metabolism*; D019897:Periplasm / Q000378:metabolism; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins / Q000378:metabolism
D029968:Escherichia coli Proteins; C517779:FlgD protein, E coli; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; D000469:Alkaline Phosphatase; C114089:phoA protein, E coli