Deletion of the Candida glabrata ERG3 and ERG11 genes: Effect on cell viability, cell growth, sterol composition, and antifungal susceptibility

A. Geber, C. A. Hitchcock, J. E. Swartz, F. S. Pullen, K. E. Marsden, K. J. Kwon-Chung, J. E. Bennett

Research output: Contribution to journalArticlepeer-review

Abstract

We have cloned and sequenced the structural genes encoding the Δ sterol desaturase (ERG3 gene) and the 14α-methyl sterol demethylase (ERGII gene) from Candida glabrata L5 (leu2). Single and double mutants of these genes were created by gene deletion. The phenotypes of these mutants, including sterol profiles, aerobic viabilities, antifungal susceptibilities, and generation times, were studied. Strain L5D (erg3Δ::LEU2) accumulated mainly ergosta-7,22-dien-3β-ol, was aerobically viable, and remained susceptible to antifungal agents but had a slower generation time than its parent strain. L5LUD (LEU2 erg11Δ::URA3) strains required medium supplemented with ergosterol and an anaerobic environment for growth. A spontaneous aerobically viable mutant, L5LUD40R (LEU2 erg11Δ::URA3), obtained from L5LUD (LEU2 erg11Δ::URA3), was found to accumulate lanosterol and obtusifoliol, was resistant to azole antifungal agents, demonstrated some increase in resistance to amphotericin B, and exhibited a 1.86-fold increase in generation time in comparison with L5 (leu2). The double-deletion mutant L5DUD61 (erg3Δ::LEU2 erg11Δ::URA3) was aerobically viable, produced mainly 14α-methyl fecosterol, and had the same antifungal susceptibility pattern as L5LUD40R (LEU2 erg11Δ::URA3), and its generation time was threefold greater than that of L5 (leu2). Northern (RNA) analysis revealed that the single- deletion mutants had a marked increase in message fur the undeleted ERG3 and ERG11 genes. These results indicate that differences in antifungal susceptibilities and the restoration of aerobic viability exist between the C. glabrata ergosterol mutants created in this study and those sterol mutants with similar genetic lesions previously reported fur Saccharomyces cerevisiae.

Original languageEnglish (US)
Pages (from-to)2708-2717
Number of pages10
JournalAntimicrobial agents and chemotherapy
Volume39
Issue number12
DOIs
StatePublished - 1995

ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)
  • Infectious Diseases

Fingerprint

Dive into the research topics of 'Deletion of the Candida glabrata ERG3 and ERG11 genes: Effect on cell viability, cell growth, sterol composition, and antifungal susceptibility'. Together they form a unique fingerprint.

Cite this