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Biogenesis of T pili in Agrobacterium tumefaciens requires precise VirB2 propilin cleavage and cyclization.

ABSTRACT: VirB2 propilin is processed by the removal of a 47-amino-acid signal peptide to generate a 74-amino-acid peptide product in both Escherichia coli and Agrobacterium tumefaciens. The cleaved VirB2 protein is further cyclized to form the T pilin in A. tumefaciens but not in E. coli. Mutations in the signal peptidase cleavage sequence of VirB2 propilin cause the formation of aberrant T pilin and also severely attenuate virulence. No T pilus was observed in these mutants. The potential role of the exact VirB2 propilin cleavage and cyclization in T pilus biogenesis and virulence is discussed.

SUBMITTER: Lai EM

PROVIDER: S-EPMC134783 | biostudies-literature | 2002 Jan

REPOSITORIES: biostudies-literature

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Biogenesis of T pili in Agrobacterium tumefaciens requires precise VirB2 propilin cleavage and cyclization.

Lai Erh-Min EM Eisenbrandt Ralf R Kalkum Markus M Lanka Erich E Kado Clarence I CI

Journal of bacteriology 20020101 1

VirB2 propilin is processed by the removal of a 47-amino-acid signal peptide to generate a 74-amino-acid peptide product in both Escherichia coli and Agrobacterium tumefaciens. The cleaved VirB2 protein is further cyclized to form the T pilin in A. tumefaciens but not in E. coli. Mutations in the signal peptidase cleavage sequence of VirB2 propilin cause the formation of aberrant T pilin and also severely attenuate virulence. No T pilus was observed in these mutants. The potential role of the ex ...[more]

PMID: 11741876

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