Transport and Polymerization of Porphyromonas gingivalis Type V Pili

Adhesive pili (or fimbriae) in bacteria are classified into five types, among which type V pili have been most recently described. Type V pili differ from other pili types with respect to transport mechanism, structure, and pilin synthesis. Genes of type V pili are restricted to the phylum Bacteroidetes. Protein subunits that compose type V pili are transported to the cell surface as lipoprotein precursors and then polymerized into a pilus through a strand-exchange mechanism, which is demonstrated by several experiments, including palmitic acid labeling and Cys-Cys cross-linking analysis. Here, we describe the use of these methods to analyze type V pili.