Multi-omics analysis revealed oil accumulation and compositional remodeling in Rhodosporidium toruloides under nitrogen limitation.

Abstract

Microbial lipids from oleaginous yeasts are promising sustainable alternatives for biofuel and food applications. However, rational engineering requires a comprehensive understanding of both lipid yield and molecular composition, together with their regulatory basis. In this study, high-coverage lipidomics integrated with stage-resolved transcriptomics was applied to Rhodosporidium toruloides under nitrogen limitation. Lipidomic analysis revealed a two-phase pattern characterized by rapid triacylglycerol accumulation followed by compositional remodeling. During the accumulation window, fatty acid class distribution and derived oil parameters showed palm-oil-like compositional features, particularly in terms of saturation balance and unsaturation-related indices. Transcriptomic analysis linked these phenotypic changes to distinct regulatory modules associated with lipid assembly and turnover. These findings suggest that lipid quantity and composition are differently regulated and may be modulated through cultivation-stage control, providing a phenotypic and regulatory basis for rational engineering of microbial oils with defined functional profiles.