Structural and functional diversity of metalloproteinases encoded by the Bacteroides fragilis pathogenicity island

Sergey A Shiryaev1, Alexander E Aleshin, Norihito Muranaka

  • 1Sanford-Burnham Medical Research Institute, La Jolla, CA, USA.

The FEBS Journal
|April 5, 2014
PubMed

Insights

Bacteroides fragilis virulence factors, metalloproteinase II (MPII) and fragilysin (FRA), have distinct evolutionary paths. Their unique prodomain structures are crucial for pathogenicity in B. fragilis infections.

Area of Science:

  • Microbiology
  • Structural Biology
  • Evolutionary Biology

Background:

  • Bacteroides fragilis is a major cause of anaerobic infections.
  • A pathogenicity island distinguishes virulent B. fragilis strains, encoding metalloproteinase II (MPII) and fragilysin (FRA).

Discussion:

  • The crystal structure of MPII was determined at 2.13 Å resolution.
  • Cleavage preferences of MPII and FRA3 were characterized using a high-throughput peptide assay.
  • MPII's catalytic domain evolution traces to human and archaebacterial proteinases.
  • The prodomain fold is specific to MPII and FRA, suggesting adaptation for B. fragilis pathogenicity.

Key Insights:

  • MPII and FRA3 catalytic domains evolved distinctly from their shared prodomain.
  • The prodomain's evolution is specifically linked to B. fragilis pathogenicity.
  • Understanding these proteases offers insights into virulence mechanisms.

Outlook:

  • Further research into metalloproteinase evolution and activation mechanisms.
  • Potential for novel therapeutic targets against B. fragilis infections.

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