The primary component of the sex pilus encoded by IncP (RP4) and Ti plasmids has been identified as a circular pilin protein with a peptide bond between the amino and carboxyl terminus. Here, we review the key experiments that led to this discovery, and the present mechanistic model for pilin-precursor processing and the cyclization reaction. In addition, we discuss the implications for horizon...

Recombination-dependent alterations of their expressed pilin gene (pilE) enable gonococci to synthesize a myriad of structurally/antigenically different pili and to reversibly switch their pilus production on and off. These changes have been ascribed both to DNA transformation and to intragenomic recombination between pilE and silent pilin genes (pilS). We examined the pilus changes in gonococc...

Cytoplasmic dynein light chain 1 (DYNLL1) is a component of large protein complex, which is implicated in cargo transport processes, and is known to interact with many cellular and viral proteins through its short consensus motif (K/R)XTQT. Still, it remains to be explored that bacterial proteins also exhibit similar recognition sequences to make them vulnerable to host defense mechanism. We em...

Pili and pilin antigenic variation play important roles in adhesion of Neisseria meningitidis (MC) to human epithelial and endothelial cells. We recently identified one pilin variant that confers high adhesiveness of MC to human epithelial cells in culture. However, other factor(s) also play a role in MC adhesiveness, since some nonadhesive variants of MC strain 8013 are piliated and produce th...

Posttrial assessment of a vaccine's selective pressure on infecting strains may be realized through a bioinformatic tool such as parsimony phylogenetic analysis. Following a failed gonococcal pilus vaccine trial of Neisseria gonorrhoeae, we conducted a phylogenetic analysis of pilin DNA and predicted peptide sequences from clinical isolates to assess the extent of the vaccine's effect on the ty...

PilO of Pseudomonas aeruginosa 1244 catalyses the attachment of an O-antigen repeating unit to the beta-carbon of the pilin C-terminal residue, a serine. The present study was conducted to locate the regions of this enzyme important in catalysis and to establish the cellular location of the pilin glycosylation reaction. While PilO was not detectable in extracts of P. aeruginosa or Escherichia c...