Propeptide processing and proteolytic activity of proenzymes of the staphylococcal and enterococcal GluV8-family protease

Indian J Biochem Biophys. 2012 Dec;49(6):421-7.

Abstract

Proenzymes with various lengths of propeptides have been observed in GluV8 from Staphylococcus aureus and GluSE from S. epidermidis. However, the production mechanism of these proenzymes and roles of truncated propeptides have yet to be elucidated. Here we demonstrate that shortening of propeptide commonly occurs in an auto-catalytic manner in GluV8-family members, including those from coagulase negative Staphylococci and Enterococcus faecalis. Accompanied with propeptide shortening, the pro-mature junction (Asn/Ser_1-Val1) becomes more susceptible towards the hetero-catalytic maturation enzymes. The auto-catalytic propeptide truncation is not observed in Ser169Ala inert molecules of GluV8-family members. A faint proteolytic activity of proenzymes from Staphylococcus caprae and E. faecalis is detected. In addition, proteolytic activity of proenzyme of GluV8 carrying Arg-3AlaAsn.1 is demonstrated with synthetic peptide substrates LLE/Q-MCA. These results suggest that GluV8-family proenzymes with shortened propeptides intrinsically possess proteolytic activity and are involved in the propeptide shortening that facilitates the final hetero-catalytic maturation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Enterococcus / drug effects
  • Enterococcus / enzymology*
  • Enterococcus / genetics
  • Enzyme Precursors / metabolism*
  • Immunoblotting
  • Molecular Sequence Data
  • Mutagenesis
  • Mutation / genetics
  • Peptide Fragments / metabolism*
  • Protein Processing, Post-Translational*
  • Proteolysis
  • Sequence Homology, Amino Acid
  • Serine Endopeptidases / genetics
  • Serine Endopeptidases / metabolism*
  • Staphylococcus aureus / drug effects
  • Staphylococcus aureus / enzymology*
  • Staphylococcus aureus / genetics
  • Staphylococcus epidermidis / drug effects
  • Staphylococcus epidermidis / enzymology*
  • Staphylococcus epidermidis / genetics
  • Thermolysin / pharmacology

Substances

  • Enzyme Precursors
  • Peptide Fragments
  • Serine Endopeptidases
  • glutamyl endopeptidase
  • Thermolysin