AUTHOR=Prasath Krishnan Ganesh , Tharani Hariharan , Kumar Mourya Suraj , Pandian Shunmugiah Karutha 

TITLE=Palmitic Acid Inhibits the Virulence Factors of Candida tropicalis: Biofilms, Cell Surface Hydrophobicity, Ergosterol Biosynthesis, and Enzymatic Activity

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.00864

DOI=10.3389/fmicb.2020.00864

ISSN=1664-302X

ABSTRACT=<p>Biofilm is the fortitude of <italic>Candida</italic> species infections which eventually causes candidiasis in human. <italic>C. tropicalis</italic> is one of the predominant <italic>Candida</italic> species commonly found in systemic infections, next to <italic>C. albicans</italic>. In <italic>Candida</italic> species, biofilm maturity initiates irreversible surface attachment of cells and barricades the penetration of conventional antifungals. Hence, the current study investigated the antifungal and antivirulence potency of palmitic acid (PA) against <italic>C. tropicalis</italic> mature biofilm and its associated virulence factors. <italic>In vitro</italic> results revealed an effective inhibition of biofilm in PA-treated <italic>C. tropicalis</italic>, compared to <italic>C. albicans</italic> and <italic>C. glabrata</italic>. Also, PA reduced <italic>C. tropicalis</italic> mature biofilm at various time points. Further, PA treatment triggered apoptosis in <italic>C. tropicalis</italic> through ROS mediated mitochondrial dysfunction as demonstrated by confocal microscopic observation of PI, DAPI and DCFDA staining. PA regulated other virulence factors such as cell surface hydrophobicity, ergosterol biosynthesis, protease and lipase after 48 h of treatment. Downregulation of <italic>ERG11</italic> (Lanosterol 14-alpha demethylase) was contributed to the reduction of ergosterol in PA-treated <italic>C. tropicalis</italic>. However, enhanced hyphal growth was observed in PA-treated <italic>C. tropicalis</italic> through upregulation <italic>HWP1</italic> (Hyphal wall protein) and <italic>EFG1</italic> (Enhanced filamentous growth). This study highlighted the antibiofilm and antivirulence potency of PA against <italic>C. tropicalis</italic>. Hence, PA could be applied synergistically with other antifungal agents to increase the efficacy for regulating NCAC infections.</p>