, Volume 35, Issue 3, pp 257–262

Cloning and sequencing of the Candida albicans C-4 sterol methyl oxidase gene (ERG25) and expression of an ERG25 conditional lethal mutation in Saccharomyces cerevisiae

  • Matthew A. Kennedy
  • Theresa A. Johnson
  • N. Douglas Lees
  • Robert Barbuch
  • James A. Eckstein
  • Martin Bard


The ERG25 gene encoding the Candida albicans C-4 sterol methyl oxidase was cloned and sequenced by complementing a Saccharomyces cerevisiae erg25 mutant with a C. albicans genomic library. The Erg25p is comprised of 308 amino acids and shows 65 and 38% homology to the enzymes from S. cerevisiae and Homo sapiens, respectively. The protein contains three histidine clusters common to nonheme iron-binding enzymes and an endoplasmic reticulum retrieval signal as do the proteins from S. cerevisiae and humans. A temperature-sensitive (ts) conditional lethal mutation of the C. albicans ERG25 was isolated and expressed in S. cerevisiae. Sequence analysis of the ts mutant indicated an amino acid substitution within the region of the protein encompassed by the histidine clusters involved in iron binding. Results indicate that plasmid-borne conditional lethal mutants of target genes have potential use in the rescue of Candida mutations in genes that are essential for viability.



C-4 methyl oxidase gene


C-3 sterol dehydrogenase


gas chromatography

plasmid pCERG25

the original complementing clone of 4kb in the Candida albicans shuttle vector YPB1


synthetic dropout




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Copyright information

© AOCS Press 2000

Authors and Affiliations

  • Matthew A. Kennedy
    • 2
  • Theresa A. Johnson
    • 2
  • N. Douglas Lees
    • 2
  • Robert Barbuch
    • 1
  • James A. Eckstein
    • 1
  • Martin Bard
    • 2
  1. 1.Department of Drug Disposition, Eli Lilly and CompanyLilly Corporate CenterIndianapolis
  2. 2.Department of BiologyIndiana University Purdue University IndianapolisIndianapolis

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