Role of the intramolecular disulfide bond in FlgI, the flagellar P-ring component of Escherichia coli.

ABSTRACT: The P ring of the bacterial flagellar motor consists of multiple copies of FlgI, a periplasmic protein. The intramolecular disulfide bond in FlgI has previously been reported to be essential for P-ring assembly in Escherichia coli, because the P ring was not assembled in a dsbB strain that was defective for disulfide bond formation in periplasmic proteins. We, however, found that the two Cys residues of FlgI are not conserved in other bacterial species. We then assessed the role of this intramolecular disulfide bond in FlgI. A Cys-eliminated FlgI derivative formed a P ring that complemented the flagellation defect of our DeltaflgI strain when it was overproduced, suggesting that disulfide bond formation in FlgI is not absolutely required for P-ring assembly. The levels of the mature forms

SUBMITTER: Hizukuri Y 

PROVIDER: S-EPMC1482947 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature