Development of quick and accurate methods for identifying human pathogenic yeast by targeting the phospholipase B gene, topoisomerase II gene, Candida drug resistance gene, and species-specific ITS 2

Candida species are a major cause of mortality in immune-compromised patients with head and neck cancer. The early detection and classification of Candida species isolated from clinical samples is crucial because of their diverse antifungal resistance patterns. This study aimed to innovate a quick and species-specific PCR-based approach for identifying Candida and pink yeast in clinical specimens. The newly developed method targets Phospholipase B (PLB), Topoisomerase II, Candida Drug Resistance (CDR) genes, and species-specific Internal transcribed spacer (ITS2) genes as novel targets. In this study, we used human pathogenic yeast species identified using universal ITS1 and 4 primers, followed by DNA sequencing. A fast and species-specific molecular technique based on PCR was carried out to identify the eight most common isolated yeast species from clinical specimens, including Candida dubliniensis, C. tropicalis, C. albicans, C. parapsilosis, C. lusitaniae, C. glabrata, Cryptococcus gattii, and Rhodotorula mucilaginosa primers targeting phospholipase B (PLB), topoisomerase II, Candida Drug Resistance (CDR) and Species-specific ITS2 region. The newly developed primers successfully amplified the targeted regions by PCR, resulting in the identification of the selected species. No cross-amplification was observed in yeast or other Candida species. The amplified products were subsequently confirmed using DNA Sanger sequencing. The study suggests that species-specific primers for several genes provide a novel approach for identifying and detecting yeast species with medicinal significance in clinical samples.