Quantitative proteome analysis revealed metabolic changes in Arthrospira platensis in response to selenium stress

Due to its high nutritional value and selenium tolerance, selenium-enriched Arthrospira platensis was a promising source for dietary Se supplementation. However, the regulatory mechanism involved in selenium enrichment in A. platensis has not been completely elucidated. In this study, we investigated the changes in physiological and proteome profiles of selenium-enriched A. platensis (Se-AP). At 30 mg/mL Na 2 SeO 3 , organic selenium concentration of A. platensis was 52.94 mg/kg. Se-AP proteins exhibited stronger antioxidant activity than the native selenium-free A. platensis (AP) proteins according to total reducing power, 2,2ʹ-azinobis-3-ethylbenzothiazolin-6-sulfonic acid (ABTS) and 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging activity. Using a tandem mass tag-based (TMT) quantitative proteomics method, 948 differentially expressed proteins were identified when A. platensis was cultured with 30 mg/L Na 2 SeO 3 . Following GO functional annotation and KEGG enrichment analysis, we found that the photosynthetic and ribosome pathways were significantly inhibited, while oxidative phosphorylation, the tricarboxylic acid cycle, prokaryote carbon fixation, amino acid synthesis, ATP-binding cassette (ABC) transporters, and antioxidant activity were markedly enhanced, improving the adaptation of A. platensis under selenium stress. Our findings will contribute to further understanding the physiological response of A. platensis against selenium stress, providing a potential strategy for developing selenium-enriched A. platensis . Graphical abstract