The gene encoding the prepilin peptidase involved in biosynthesis of piluscolonization factor antigen III (CFA/III) of human enterotoxigenic Escherichia coli

Citation
T. Taniguchi et al., The gene encoding the prepilin peptidase involved in biosynthesis of piluscolonization factor antigen III (CFA/III) of human enterotoxigenic Escherichia coli, MICROB IMMU, 43(9), 1999, pp. 853-861
Citations number
42
Categorie Soggetti
Microbiology
Journal title
MICROBIOLOGY AND IMMUNOLOGY
ISSN journal
03855600 → ACNP
Volume
43
Issue
9
Year of publication
1999
Pages
853 - 861
Database
ISI
SICI code
0385-5600(1999)43:9<853:TGETPP>2.0.ZU;2-R
Abstract
The assembly of pilus colonization factor antigen III (CFA/III) of human en terotoxigenic Escherichia coli requires the processing of CFA/III major pil in (CofA) by a peptidase, likely another type IV pilus formation system. We stern blot analysis of CofA reveals that CofA is produced initially as a 26 .5-kDa preform pilin (prepilin) and then processed to 20.5-kDa mature pilin by a prepilin peptidase. This processing is essential for exportation of t he CofA from the cytoplasm to the periplasm. In this experiment, the struct ural gene, cofP, encoding CFA/III prepilin peptidase which cleavages at the Gly-30-Met-31 junction of CofA was identified, and the nucleotide sequence of the gene was determined. cofP consists of 819 bp encoding a 273-amino a cid protein with a relative molecular mass of 30,533 Da. CofP is predicted to be localized in the inner membrane based on its hydropathy index. The am ino acid sequence of CofP shows a high degree of homology with other prepil in peptidases which play a role in the assembly of type IV pill in several gram-negative bacteria.