Publication

The expression of the secreted aspartyl proteinases Sap4 to Sap6 from Candida albicans in murine macrophages

Journal Paper/Review - May 1, 1998

Units
PubMed

Citation
Borg-von Zepelin M, Beggah S, Boggian K, Sanglard D, Monod M. The expression of the secreted aspartyl proteinases Sap4 to Sap6 from Candida albicans in murine macrophages. Mol Microbiol 1998; 28:543-54.
Type
Journal Paper/Review (English)
Journal
Mol Microbiol 1998; 28
Publication Date
May 1, 1998
Issn Print
0950-382X
Pages
543-54
Brief description/objective

Medically important yeasts of the genus Candida secrete aspartyl proteinases (Sap), which are of particular interest as virulence factors. Six closely related gene sequences, SAP1 to SAP6, for secreted proteinases are present in Candida albicans. The methylotrophic yeast Pichia pastoris was chosen as an expression system for preparing substantial amounts of each Sap isoenzyme. Interestingly, Sap4, Sap5 and Sap6, which have not yet been detected in C. albicans cultures in vitro, were produced as active recombinant enzymes. Different Sap polyclonal antibodies were raised in rabbits and tested before further application by enzyme-linked immunosorbent assay (ELISA) against each recombinant Sap. Two antisera recognized only Sap4 to Sap6. Using these antisera, together with sap null mutants obtained by targeted mutagenesis, we could demonstrate a high production of Sap4, Sap5 and Sap6 by C. albicans cells after phagocytosis by murine peritoneal macrophages. Furthermore, a delta sap4,5,6 null mutant was killed 53% more effectively after contact with macrophages than the wild-type strain. These results support a role for Sap4 to Sap6 in pathogenicity.