Evaluating the stress response in Candida albicans by data independent acquisition (DIA) proteomics

Candida albicans is a fungal opportunistic pathogen responsible for cause severe infections in immunocompromised patients. Despite nowadays an effective antifungal armoury is available, the emergence of antifungal resistance is promoting the urge to develop alternative treatments to combat this fungal pathogen. For this purpose it is essential to go deepen in the knowledge of C. albicans response to several stressors. With this aim we performed a proteomic study of C. albicans exposed to 5 and 10 mM of hydrogen peroxide and 40 and 60 mM of acetic acid taking advantage of data independent acquisition mass spectrometry. Four biological replicates of each condition were analysed. For protein identification we used a C. albicans spectral library previously constructed by DDA analysis allowing the DIA quantitation of nearby 2000 proteins. Changes in protein abundance after the treatments reflected highly different proteomic patterns after each treatment. The exposure of C. albicans to hydrogen peroxide led to an increase in many proteins related to oxidative stress response, proteasome and protein folding while few proteins from mitochondria decreased their abundance. In contrast, acetic acid treatment triggered the decrease in the abundance of proteins related to aminoacid biosynthesis, actin polymerization, oxidative stress response and proteasome. This extensive proteomic study provided valuable information for the development of new drug targets against decisive proteins for cell survival.