Phenotypic and molecular detection of virulence factor genes SAP 4 and PLB in Candida albicans isolates from the Western part of India

Megha Yogesh Pawar; Swarupa Mahesh Hatolkar; Rabindra Nath Misra

doi:10.1016/j.mjafi.2020.03.023

Phenotypic and molecular detection of virulence factor genes SAP 4 and PLB in Candida albicans isolates from the Western part of India

Med J Armed Forces India. 2022 Jul;78(3):271-276. doi: 10.1016/j.mjafi.2020.03.023. Epub 2020 Jul 10.

Authors

Megha Yogesh Pawar¹, Swarupa Mahesh Hatolkar², Rabindra Nath Misra³

Affiliations

¹ Lecturer (Microbiology), Dr. D. Y. Patil Biotechnology and Bioinformatics Institute, Dr. D. Y. Patil Vidyapeeth (DPU), Tathawade, Pune, India.
² Assistant Professor (Microbiology), Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth (DPU), Pimpri, Pune, India.
³ Professor & Head (Microbiology), Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth (DPU), Pimpri, Pune, India.

Abstract

Background: Since the last two decades, substantial increase in fungal infections has been observed in immunocompromised hosts. Virulence factors of Candida albicans play a role in adherence, haemolytic activity, phenotypic switching and production of hydrolytic enzymes. The secreted aspartyl proteinases (SAP family) contribute to adhesion, tissue damage and invasion, while phospholipase (PLB) supports the hydrolysis of phospholipids. Very few studies showed the correlation of phenotypic activity and detection of genes contributing to the similar enzyme activity. Therefore, our study aimed at demonstrating correlation between in vitro phenotypic production of phospholipase and proteinase enzymes with genetic level detection of SAP and PLB genes.

Methods: The present study was carried out on a total of 799 samples over a period of one year. Culturing was carried out on Sabouraud's dextrose agar. Confirmation and speciation of Candida spp. was carried out using cornmeal agar and CHROMagar and by the germ tube test, urease test and automated identification system Vitek-2, and antifungal susceptibility testing was performed on Candida isolates. Phenotypic phospholipase and proteinase activity was analysed, and molecular detection of SAP4 and PLB genes was carried out.

Results: In our study, we have screened 799 samples for mycological protocol; of which, 269 (33.6%) were Candida species, 44% (119) of which were C. albicans. Proteinase activity was exhibited by 77 (64.7%) and phospholipase activity was exhibited by 73 (61.34%) isolates, while 46.2% exhibited both activities among the C. albicans species. The PLB gene was detected in 97.3% isolates, while SAP4 was detected in 94.7% of C. albicans isolates.

Conclusion: The study of in vitro expression of virulence factors and gene detection of C. albicans will help to improve the prognosis despite the nature of the sample.

Keywords: Candida albicans; Phospholipase; Proteinase; Secreted aspartyl proteinases; Virulence factor.