AUTHOR=Huang Mingjiao , Yang Longbing , Zhou Luoxiong , Sun Chaoqin , Zhao Wenjing , Peng Jian , Jiao Zhenlong , Tian Chunren , Guo Guo 

TITLE=Identification and functional characterization of ORF19.5274, a novel gene involved in both azoles susceptibility and hypha development in Candida albicans

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.990318

DOI=10.3389/fmicb.2022.990318

ISSN=1664-302X

ABSTRACT=<p>Azole resistance is becoming increasingly serious due to the frequent recurrence of fungal infections and the need for long-term clinical prevention. In our previous study, we discovered <italic>ORF19.5274</italic> with an unknown function by TMT<sup>™</sup> quantitative proteomics technology after fluconazole (FLC) treatment of <italic>Candida albicans</italic>. In this study, we created the target gene deletion strain using CRISPR-Cas9 editing technology to see if <italic>ORF19.5274</italic> regulates azole sensitivity. The data showed that <italic>ORF19.5274</italic> was involved in hyphal development and susceptibility to antifungal azoles. Deleting this gene resulted in defective hyphal growth in solid medium, while only a weak lag in the initiation of hyphal development and restoring hyphal growth during the hyphal maintenance phase under liquid conditions. Moreover, intracellular reactive oxygen species (ROS) assay and propidium iodide staining assays showed increased endogenous ROS levels and membrane permeability, but decreased metabolic activity of biofilm in <italic>orf19.5274Δ/Δ</italic> after treatment with FLC in comparison with either SC5314 or <italic>orf19.5274Δ/Δ::ORF19.5274</italic> strains. More importantly, <italic>orf19.5274Δ/Δ</italic> significantly enhanced the FLC efficacy against <italic>C. albicans</italic> in infected <italic>Galleria mellonella</italic> larvae. The above characteristics were fully or partially restored in the complemented strain indicating that the changes caused by <italic>ORF19.5274</italic> deletion were specific. In summary, the <italic>ORF19.5274</italic> gene is required for hyphal development of <italic>C. albicans</italic>, and is correlated with the response to antifungal azoles <italic>in vitro</italic> and <italic>in vivo</italic>. The identification of <italic>ORF19.5275</italic> is promising to expand the potential candidate targets for azoles.</p>