Integrated proteomic and metabolomic analysis to study the effects of spaceflight on Candida albicans

Abstract Background Candida albicans is an opportunistic pathogenic yeast, which could become pathogenic in various stressful environmental factors including the spaceflight environment. In this study, we aim to explore the phenotypic changes and possible mechanisms of Candida albicans after exposure to spaceflight conditions.Results The effect of Candida albicans after carried on the "SJ-10" satellite for 12 days was evaluated by proliferation, morphogenic, environmental resistance and virulence experiment. The result showed that the proliferation rate, biofilm formation, antioxidant capacity, cytotoxicity and filamentous morphology of Candida albicans were increased in the spaceflight group compared to the control group. Proteomics and metabolomics technologies were used to analyze the profiles of proteins and metabolites in Candida albicans under spaceflight conditions. Proteomic analysis identified 564 up-regulated proteins involved in ribosome, DNA replication, base excision repair and sulfur metabolism in the spaceflight group. And 345 down-regulated proteins related to metabolic processes were observed. The metabolomic analysis found 5 different expressed metabolites. The combined analysis of proteomic and metabolomic revealed the accumulation of cysteine and methionine in Candida albicans after spaceflight.Conclusions Mechanisms that could explain the results in the phenotyping experiment of Candida albicans were found through proteomic and metabolomic analysis. And our data provide an important basis for the assessment of the risk that Candida albicans could cause under spaceflight environment.