Rapid identification of Candida albicans, C. glabrata, C. parapsilosis and C. krusei by species-specific PCR of large subunit ribosomal DNA

Abstract

A rapid PCR-based method for the identification of four Candida species is described. Primers to conserved sequences in the V3 region of large subunit rDNA were used to amplify DNA from C. albicans, C. glabrata, C. parapsilosis and C. krusei. The sequences were aligned and areas of non-concordance were used to design four species-specific forward primers. In a blind study of 82 yeast strains, four PCRs based on these primers correctly identified nine C. albicans, 18 C. glabrata, 13 C. parapsilosis and 18 C. krusei strains after gel electrophoresis of amplified DNA. Furthermore, of 17 other Candida strains (10 species) and seven strains from other yeast genera (Saccharomyces, Cryptococcus and Trichosporon) only one false positive amplification product (with C. dubliniensis) was seen. These PCRs offer a rapid alternative to conventional techniques for the identification of C. albicans, C. glabrata, C. parapsilosis and C. krusei.