Development of a high-throughput screen and its use in the discovery of Streptococcus pneumoniae immunoglobulin A1 protease inhibitors

J Am Chem Soc. 2013 Jul 10;135(27):10014-7. doi: 10.1021/ja404180x. Epub 2013 Jun 28.

Abstract

Streptococcus pneumoniae relies on a number of virulence factors, including immunoglobulin A1 protease (IgA1P), a Zn(2+) metalloprotease produced on the extracellular surface of the bacteria, to promote pathogenic colonization. IgA1P exhibits a unique function, in that it catalyzes the proteolysis of human IgA1 at its hinge region to leave the bacterial cell surface masked by IgA1 Fab, enabling the bacteria to evade the host's immune system and adhere to host epithelial cells to promote colonization. Thus, S. pneumoniae IgA1P has emerged as a promising antibacterial target; however, the lack of an appropriate screening assay has limited the investigation of this metalloprotease virulence factor. Relying on electrostatics-mediated AuNP aggregation, we have designed a promising high-throughput colorimetric assay for IgA1P. By using this assay, we have uncovered inhibitors of the enzyme that should be useful in deciphering its role in pneumococcal colonization and virulence.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Biological Products / chemistry
  • Biological Products / pharmacology*
  • Dose-Response Relationship, Drug
  • High-Throughput Screening Assays
  • Molecular Structure
  • Protease Inhibitors / chemistry
  • Protease Inhibitors / pharmacology*
  • Serine Endopeptidases / metabolism*
  • Streptococcus pneumoniae / enzymology*
  • Structure-Activity Relationship

Substances

  • Biological Products
  • Protease Inhibitors
  • Serine Endopeptidases
  • IgA-specific serine endopeptidase