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.

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  • 1. Nayman AS, Zgune AY, Ertem OT, Erben N, Doyuk KE. Evaluation of risk factors in patients with candiduria. Mikrobiyol Bul 2011; 45: 318-324. 2. Sievert DM, Ricks P, Edwards JR.Antimicrobial-resistant pathogens associated with healthcare-associated infections: summary of data reported to the National Healthcare Safety Network at the Centers for Disease Control and Prevention, 2009-2010. Infect Control Hosp Epidemiol 2013; 34:1-14. 3. Pfaller MA, Diekema DJ. Epidemiology of invasive candidiasis: a persistent public health problem. Clin Microbiol Rev 2007; 20(1):133-63. 4. Kothari A, Sagar V. Epidemiology of Candida blood stream infections in a tertiary care institute in India. IJMM 2009; 27:171-172. 5. Bijender KB, Sharma S, Construction of killer industrial yeast Saccharomyces –cerevisiaehau-1 and its fermentation performance. BJM 2010; 41: 477-485. 6. Baeza ME, Sanhueza MA, Cifuentes VH. Occurrence of killer yeast strains in industrial and clinical yeast isolates. Biol Res 2008; 41: 173-182. 7. Wang XZ, Chi L, Yue JL. Purification and Characterization of killer toxin from a marine yeast Pichia anomala YF07b against the pathogenic yeast in crab. Curr Microbiol 2007; 55:396-401. 8. Jagadish C, Nidhi S, Shailpreet KS, et al. Epidemiology of Candida blood stream infections: experience of a tertiary care centre in North India. J .Infect Dev Ctries 2013; 7:670-675. 9. Clinical and Laboratory Standards Institute: Reference Method for Broth Dilution Antifungal Susceptibility Testing of Yeasts; Approved Standard- Second Edition M27-A2. National Committee for Clinical Laboratory Standards, Wayne, Pennsylvania, USA 2002.CLSI M27-A3. 10. Branchini ML, Pfaller MA, Rhine et al. Genotype variation and slime production among blood and catheter isolates of C Parapsilosis. J Clin Microbiol 1994; 32:452-6. 11. Peng Y, Chi ZM, Wang XH, Li J. Purification and molecular characterization of exo-β-1, 3-glucanases from the marine yeast WilliopsissaturnusWC91-2. Appl Microbiol Biotechnol 2009; 85: 85–94. 12. Izgu F, Altinbay D, Tureli AE. In vitro activity of Panomycin a novel exo-β-1, 3-glucanase isolated from Pichia anomala NCYC 434, against Dermatophytes. Mycoses 2006; 50: 31-34. 13. Irvine GB and Shaw C. “High-performance gel permeation chromatography of proteins and peptides on colums of TSK-G2000-SW and TSK- G3000SW: A volatile solvent giving separation based on charge and size of polypeptides” Anal Biochem 1986; 155:141-148. 14. Vesterberg O. “Isoelectric focusing of proteins”, Electrophoretic Procedures 1971; 22:389-411. 15. Izgu F, Altınbat D, Sertkaya A. Enzymic activity of the K5 type yeast killer toxin and its characterization. Biosci Biotechnol Biochem 2005; 69:2200-2206. 16. Menza N, Wanyoike W, Muturi WM. Prevalence of Vaginal Candidiasis and Determination of the Occurrence of Candida Species in Pregnant Women Attending the Antenatal Clinic of Thika District Hospital, Kenya. Open J Med Microbiol 2013; 3: 264-272. 17. Saldanha DR, Shivanand D. Candida speciation and anti-fungal susceptibility. J Clinic Diagnostic Research 2011; 5: 1177-1181. 18. Mokaddas E, Khan ZU & Ahmad S. Prevalence of Candida dubliniensis among cancer patients in Kuwait: a 5-year retrospective study. Mycoses 2011; 54, 29-34. 19. Ooga1 VB, Gikunju JK, Bii CC. Characterization and antifungal drug susceptibility of clinical isolates of Candida species. Afr J Health Sci 2011; 19:84-92. 20. Kothari A and Sagar V. Epidemiology of Candida bloodstream infections in a tertiary care institute in India. Indian J Med Microbiol 2009; 27:171–172. 21. Lortholary O, Desnos OM, SitbonK. Recent exposure to caspofungin or fluconazole influences the epidemiology of candidemia: a prospective multicenter study involving 2,441 patients. Antimicrob Agents Chemother 2011; 55:532–8. 22. Finkel JS and Mitchell AP. Genetic control of Candida albicans biofilm development. Nat Rev Microbiol 2011; 9: 109–118. 23. Tavleen J, Urhekar A, Chitra P. Study of Candida species in various clinical samples in a tertiary care hospital. DHR Intern J Med Scien 2014; 5:2. 24. Marcelo EB, Mario AS and Víctor HC. Occurrence of killer yeast strains in industrial and clinical yeast isolates. Biol Res 2008; 41:173-182. 25. Paluszynski JP, Klassen R, Meinhardt F. Pichia acacia killer system: genetic analysis of toxin immunity. Appl Environ Microbiol 2007; 73: 4373–4378. 26. Pietro B, Benedetta T and Ann EV. The use of killer sensitivity patterns for biotyping yeast strains the state of the art, potentialities and limitations. FEMS Yeast Res 2007; 7:749-760. 27. Gulbiniene G, Kondratiene I, Jokantaite T. Occurrence of killer yeast strains in fruit and berry Wine yeast populations. Food technol biotechnol 2004; 42:159-163. 28. Santos A, Mauro M, Bravo E. PMKT2, a new killer toxin from Pichia membranifaciens, and its promising biotechnological properties for control of the spoilage yeast Brettanomyces bruxellensis. Microbiol 2009; 155: 624–634.