Development of Streptococcus thermophilus lacZ as a reporter gene for Candida albicans

Microbiology (Reading). 2001 May;147(Pt 5):1189-1195. doi: 10.1099/00221287-147-5-1189.


The study of gene regulation in many organisms has been facilitated by the development of reporter genes. The authors report the use of lacZ from Streptococcus thermophilus, a gene encoding a beta-galactosidase, as a reporter for the fungal pathogen Candida albicans. As test cases, Strep. thermophilus lacZ was placed under control of three different C. albicans promoters: MAL2 (maltase), inducible by maltose; HWP1 (hyphal cell wall protein), induced by conditions that promote filamentous growth; and ACT1 (actin). These constructs were each integrated into the C. albicans genome and beta-galactosidase activity was readily detected from these strains, but only under the appropriate growth conditions. Beta-galactosidase activity could be detected by several methods: quantitative liquid assays using permeabilized cells, colorimetric assays of colonies replicated to paper filters, and in situ coloration of colonies growing on medium containing the indicator X-Gal. These results show the usefulness of STREP: thermophilus lacZ as a monitor of gene regulation in this medically important yeast.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actins / genetics
  • Candida albicans / genetics*
  • Candida albicans / metabolism
  • Fungal Proteins*
  • Genes, Reporter*
  • Lac Operon*
  • Membrane Glycoproteins / genetics
  • Promoter Regions, Genetic
  • Saccharomyces cerevisiae / genetics
  • Streptococcus / genetics*
  • alpha-Glucosidases / genetics
  • beta-Galactosidase / metabolism


  • ACT1 protein, Candida albicans
  • Actins
  • Fungal Proteins
  • HWP1 protein, Candida albicans
  • Membrane Glycoproteins
  • alpha-Glucosidases
  • beta-Galactosidase