title: Acid proteinase secreted by Candida tropicalis: functional analysis of preproregion cleavages in C. tropicalis and Saccharomyces cerevisiae.
abstract: The 40 kDa secreted aspartyl proteinase (Sapt1) of Candida tropicalis is a pepsin-like enzyme encoded by the SAPT1 gene. According to the deduced amino acid sequence. Sapt1 has a putative preproregion of 60 amino acids preceding the mature enzyme. Maturation and processing of Sapt1 was analysed in C. tropicalis and Saccharomyces cerevisiae strains expressing wild-type or mutated forms of SAPT1. In S. cerevisiae, the glycosylated 46 kDa proenzyme was converted to the mature 40 kDa form of Sapt1 by KEX2-dependent proteolytic cleavage following the Lys59-Arg60 sequence. The replacement of Lys59-Arg60 by Lys59-Gly60 revealed that the precursor can be processed by an autocatalytic cleavage. This alternative processing pathway to produce mature Sapt1 is less efficient than the Kex2-mediated pathway. Finally, it was shown that in C. tropicalis and S. cerevisiae the removal of the proregion was a prerequisite for the secretion of Sapt1.
authors.affiliation: Institut de Microbiologie, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland.|Laboratoire de Mycologie, Service de Dermatologie, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Togni
authors.affiliation: Institut de Microbiologie, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland.
authors.forename: Dominique
authors.initials: D
authors.lastname: Sanglard
authors.affiliation: Laboratorium für Biochemie, ETH-Zentrum, 8092 Zürich, Switzerland.
authors.forename: Manfredo
authors.initials: M
authors.lastname: Quadroni
authors.affiliation: Laboratory of Protein Crystallography, Protein Studies Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA.
authors.forename: Stephen I
authors.initials: SI
authors.lastname: Foundling
authors.affiliation: Laboratoire de Mycologie, Service de Dermatologie, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland.
authors.forename: Michel
authors.initials: M
authors.lastname: Monod
mesh_terms: D002175:Candida / Q000201:enzymology*; D010450:Endopeptidases / Q000235:genetics / Q000378:metabolism*; D004792:Enzyme Precursors / Q000235:genetics / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D010957:Plasmids / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
chemical_list: D004792:Enzyme Precursors; D010450:Endopeptidases