Single-residue changes in the C-terminal disulfide-bonded loop of the Pseudomonas aeruginosa type IV pilin influence pilus assembly and twitching motility.

ABSTRACT: PilA, the major pilin subunit of Pseudomonas aeruginosa type IV pili (T4P), is a principal structural component. PilA has a conserved C-terminal disulfide-bonded loop (DSL) that has been implicated as the pilus adhesinotope. Structural studies have suggested that DSL is involved in intersubunit interactions within the pilus fiber. PilA mutants with single-residue substitutions, insertions, or deletions in the DSL were tested for pilin stability, pilus assembly, and T4P function. Mutation of either Cys residue of the DSL resulted in pilins that were unable to assemble into fibers. Ala replacements of the intervening residues had a range of effects on assembly or function, as measured by changes in surface pilus expression and twitching motility. Modification of the C-terminal P-X-X-C type I

SUBMITTER: Harvey H 

PROVIDER: S-EPMC2795284 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature