The PapG-adhesin at the tip of P-fimbriae provides Escherichia coli with a competitive edge in experimental bladder infections of cynomolgus monkeys.
Human urinary tract infection is an infectious disease that depends on a series of host-microbial interactions. The bacteria first colonize the colon and then the periurethral/vaginal areas; they ascend to and infect first the bladder and then the kidneys. Expression of Escherichia coli P-fimbriae constitutes the strongest correlation to renal pathogenicity, but is also related to first-time cystitis in children. The role of P-fimbriae in the preceding steps in the infectious process is unknown. To examine this, we constructed, from a P-fimbriated E. coli strain with a class II G-adhesin preferentially binding to globoside, one isogenic mutant lacking the G-adhesin and another isogenic mutant in which we replaced the papG class II allele with a class III adhesin preferentially binding to the Forssman antigen. We report here the comparison of the adhesin knockout mutant (DS17-8) and the class-switch mutant (DS17-1) with the wild-type (DS17) for in vivo colonization of the gut, vagina, and bladder of cynomolgus monkeys. It was recently shown that the class II tip G-adhesin is a prerequisite for acute pyelonephritis to occur in the monkey model in the absence of other kidney-specific adhesins or obstruction of the urinary flow. Here we show that it is not required for bladder infection but gives a competitive advantage in mixed infections. In the vagina and colon, the G-adhesin gives no competitive advantage.
D018830:Adhesins, Escherichia coli / Q000502:physiology*; D000818:Animals; D001422:Bacterial Adhesion; D017931:DNA Primers / Q000737:chemistry; D004927:Escherichia coli Infections / Q000382:microbiology*; D005260:Female; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial / Q000502:physiology*; D007422:Intestines / Q000382:microbiology*; D008252:Macaca fascicularis; D016297:Mutagenesis, Site-Directed; D013329:Structure-Activity Relationship; D001743:Urinary Bladder / Q000382:microbiology*; D014621:Vagina / Q000382:microbiology*
D018830:Adhesins, Escherichia coli; D017931:DNA Primers; C092426:PapG protein, E coli; D036781:Fimbriae Proteins