The Pil3 pilus of Streptococcus gallolyticus binds to intestinal mucins and to fibrinogen

Gut Microbes. 2016 Nov;7(6):526-532. doi: 10.1080/19490976.2016.1239677. Epub 2016 Sep 22.

Abstract

Streptococcus gallolyticus is a commensal bacterium responsible for infectious endocarditis in the elderly, which has frequently been associated with colonic carcinoma. Whether this species is a cause or a consequence of colorectal cancer remains unknown. We recently demonstrated that S. gallolyticus Pil3 pilus is required for adhesion to colonic mucus and for colonization of mouse distal colon. We show here that Pil3 pilus binds equally well to human colonic mucins derived from HT29-MTX cells and to human stomach mucins from healthy donors. In addition, we have found that Pil3 also binds to human fibrinogen, which expands the repertoire of Pil3 host ligands.

Keywords: MUC2; MUC5AC; Pil3 pilus; S. bovis; S. gallolyticus; colon; colonization; fibrinogen; mucins.

MeSH terms

  • Animals
  • Bacterial Adhesion
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Cell Line
  • Fibrinogen / metabolism*
  • Fimbriae Proteins / genetics
  • Fimbriae Proteins / metabolism*
  • Humans
  • Intestinal Mucosa / metabolism
  • Intestines / microbiology*
  • Mice
  • Mucins / metabolism*
  • Streptococcal Infections / metabolism*
  • Streptococcal Infections / microbiology*
  • Streptococcus gallolyticus / genetics
  • Streptococcus gallolyticus / metabolism*

Substances

  • Bacterial Proteins
  • Mucins
  • Fimbriae Proteins
  • Fibrinogen