Toshio Kanbe1, Keisuke Kurimoto, Hisao Hattori, Takako Iwata, Akihiko Kikuchi. 1. Division of Molecular Mycology and Medicine, Department of Advanced Medical Science, Center for Neurological Disease and Cancer, Nagoya Graduate School of Medicine, 65 Tsurumai, Showa-ku, Nagoya, Aichi 466-8550, Japan. tkanbe@med.nagoya-u.ac.jp
Abstract
BACKGROUND: Candidiasis is caused by several Candida species, of which Candida stellatoidea and C. dubliniensis are phenotypically close to C. albicans. Although current molecular biology-based techniques can distinguish between C. albicans and C. dubliniensis, a convenient tool that can distinguish C. stellatoidea from C. albicans has not yet been developed. OBJECTIVE: To develop a system that can simply, rapidly and specifically distinguish C. albicans from the related Candida species C. stellatoidea and C. dubliniensis. MATERIALS: Genomic DNAs were purified from various yeast species and amplified by primers specific for the repetitive sequence (RPS) of C. albicans. The PCR products were purified and sequenced in order to test the specificity of the PCR amplification. RESULTS: The PCR primers only amplified several products from C. albicans, C. stellatoidea and C. dubliniensis. Sequence analysis of the products revealed that C. stellatoidea and C. dubliniensis both had RPSs including alt repeats, similar to C. albicans. After the PCR amplification, each of the three Candida species showed a unique amplification profile. Furthermore, RFLP analysis of the PCR products using EcoRI and ClaI produced species-specific restriction profiles. CONCLUSIONS: This PCR-based technique targeting the alt repeats in the RPS is useful as a tool for the rapid identification and distinction of C. albicans, C. stellatoidea and C. dubliniensis.
BACKGROUND: Candidiasis is caused by several Candida species, of which Candida stellatoidea and C. dubliniensis are phenotypically close to C. albicans. Although current molecular biology-based techniques can distinguish between C. albicans and C. dubliniensis, a convenient tool that can distinguish C. stellatoidea from C. albicans has not yet been developed. OBJECTIVE: To develop a system that can simply, rapidly and specifically distinguish C. albicans from the related Candida species C. stellatoidea and C. dubliniensis. MATERIALS: Genomic DNAs were purified from various yeast species and amplified by primers specific for the repetitive sequence (RPS) of C. albicans. The PCR products were purified and sequenced in order to test the specificity of the PCR amplification. RESULTS: The PCR primers only amplified several products from C. albicans, C. stellatoidea and C. dubliniensis. Sequence analysis of the products revealed that C. stellatoidea and C. dubliniensis both had RPSs including alt repeats, similar to C. albicans. After the PCR amplification, each of the three Candida species showed a unique amplification profile. Furthermore, RFLP analysis of the PCR products using EcoRI and ClaI produced species-specific restriction profiles. CONCLUSIONS: This PCR-based technique targeting the alt repeats in the RPS is useful as a tool for the rapid identification and distinction of C. albicans, C. stellatoidea and C. dubliniensis.