Abstract

Metabolomics based on LC-MS was used for the analysis of the fermentation of Proteiniphilum acetatigenes PSB-W treated by different culture time and different light intensity. 26 putative metabolites were detected in samples treated by different culture time. Most of the components were produced in the metabolic activity in order to participate in the whole life process of bacteria. Compared with samples treated with light intensity, a total of 37 metabolites were detected and analyzed. Only 10 compounds were detected in 1000 Lux group, which is significantly less than 1500 Lux group. The metabolite data of light groups were passed through principal component analysis (PCA) and differential metabolites were screened for each comparison group by using the Volcano Plot model. The differential metabolites were annotated by the Kyoto Encyclopedia of Genes and Genomes (KEGG) database and 7 differential metabolites related to the carotenoid synthesis enrichment pathway were screened. The results showed that carotenoids synthesis may occur during the stationary phase of bacterial growth. The precursor of carotenoid synthesis of photosynthetic bacteria is isopentenyl diphosphate (IPP) synthesized by acetyl coenzyme A under the catalysis of HMG CoA reductase. It is preliminarily clarified that it is the accumulation mechanism of bacterial carotenoid biosynthesis and provides a new clue for the comprehensive study of the synthesis and regulation mechanism of carotenoids.

Key words: Carotenoids, metabolomics analysis, Proteiniphilum acetatigenes PSB-W.