Bioregulatory Role of Wickerhamomyces anomalus Killer Toxin against Pathogenic Members of the Genus Candida

Abstract

Objectives: Candida species are endogenous fungus causing both mucosal and invasive infections. With the increasing rate of non-albicans Candida infections with varying susceptibilities, early and accurate species identification would help the clinician in befitting therapeutic management. So the interest in natural products secreted by a fungus Wickerhamomyces anomalus itself as an antimicrobial agent against pathogenic Candida species has evaluated in the present study. Methods: A total of 336 Candida species isolated from various clinical samples were included in the study. Candida identification, antifungal susceptibility was done by standard procedures. The environmental yeast killer toxin Wickerhamomyces anomalus was purified and the killer toxin assay against Candida species was done by standard procedures. Results: The predominant Candida species were Candida albicans (31%), but the emergence of non-albicans Candida also noted with 69%. Total antifungal resistance was 117 (35%) with fluconazole resistance in Candida albicans 13 (13%) and in non-albicans Candida were 50 (21%). The characterization of W. anomalus toxin has revealed that it is a glycoprotein of having 42.6 kDa active at pH 5.5 and temperatures 250 C. Candida isolates showed 292 (87%) sensitivity to the killer toxin. Conclusions: The study emphasizes the need for rapid and precise speciation and antifungal susceptibility of Candida isolates for effective treatment and management strategies.Our study proved the antifungal ability of W. anomalus and this resource can be used for alternative treatment of candidiasis with further assessments. J Microbiol Infect Dis 2019; 9(3):155-160.