Degradation of the extracellular matrix components by bacterial-derived metalloproteases: implications for inflammatory bowel diseases

Inflamm Bowel Dis. 2011 May;17(5):1189-200. doi: 10.1002/ibd.21475. Epub 2010 Sep 17.


Background: Proteolytic degradation of the extracellular matrix, a feature of mucosal homeostasis and tissue renewal, also contributes to the complications of intestinal inflammation. Whether this proteolytic activity is entirely host-derived, or, in part, produced by the gut microbiota, is unknown.

Methods: We screened the bacterial colonies for gelatinolytic activity from fecal samples of 20 healthy controls, 23 patients with ulcerative colitis, and 18 with Crohn's disease (CD). In addition, the genes encoding metalloproteases were detected by conventional or real-time polymerase chain reaction (PCR).

Results: Gelatinolytic activity was found in approximately one-quarter of samples regardless of the presence of inflammation and without any attempt to enhance the sensitivity of the culture-based screen. This was associated with a diversity of bacteria, particularly in CD, but was predominantly linked with Clostridium perfringens. Culture supernatants from C. perfringens degraded gelatin, azocoll, type I collagen, and basement membrane type IV collagen, but different isolates varied in the degree of proteolytic activity. Results were confirmed by detection of the C. perfringens colA gene (encoding collagenase) in fecal DNA, again regardless of the presence or absence of inflammation. However, the biologic significance and potential implications of microbial-derived proteolytic activity were confirmed by reduced transepithelial resistance (TER) after exposure of rat distal colon to culture supernatants of C. perfringens in Ussing chambers.

Conclusions: The study shows that microbial-derived proteolytic activity has the capacity to contribute to mucosal homeostasis and may participate in the pathogenesis of inflammatory bowel disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Basement Membrane / metabolism
  • Basement Membrane / pathology
  • Clostridium perfringens / enzymology*
  • Clostridium perfringens / genetics
  • Colitis, Ulcerative / metabolism
  • Colitis, Ulcerative / microbiology*
  • Colitis, Ulcerative / pathology
  • Collagen Type IV / metabolism
  • Crohn Disease / metabolism
  • Crohn Disease / microbiology*
  • Crohn Disease / pathology
  • Extracellular Matrix / enzymology
  • Extracellular Matrix / pathology
  • Feces / microbiology
  • Gastrointestinal Tract / microbiology
  • Humans
  • In Vitro Techniques
  • Metagenome / physiology*
  • Metalloendopeptidases / genetics
  • Metalloendopeptidases / metabolism*
  • Metalloproteases / genetics
  • Metalloproteases / metabolism
  • Microbial Collagenase / genetics
  • Microbial Collagenase / metabolism*
  • Microbiological Techniques
  • Middle Aged
  • Polymerase Chain Reaction
  • Rats
  • Staphylococcus epidermidis / enzymology
  • Staphylococcus epidermidis / genetics


  • Bacterial Proteins
  • Collagen Type IV
  • Metalloproteases
  • Metalloendopeptidases
  • SepA protein, Staphylococcus epidermidis
  • Microbial Collagenase
  • kappa-toxin, Clostridium perfringens