Effects of FNR, Arca and oxygen on the synthesis of bacterial cellulose

Purpose:The oxygen-regulated genes FNR and ARCA were combined with Komagataeibacter xylinus CGMCC 2955 to provide a new perspective for the study of the mechanism of oxygen environment on BC synthesis. Methods:The FNR and Arca overexpressing strains and the control strains were fermented under different partial oxygen pressures. The bacterial cellulose membrane in the logarithmic period of fermentation was enzymolyzed, and the bacteria were collected for transcriptome analysis.Sequencing was performed with Illumina and transcriptome analysis was performed on the bacteria under different conditions. Results:Transcriptome sequencing was performed using Illumina high-throughput sequencing technology on K. xylinus cultured under different oxygen tensions. The differentially expressed genes in the arcA overexpressing strains were mainly in the sulfur metabolism, two-component system, purine metabolism, and amino acid metabolism pathways compared to the control strains. Analysis showed that the arcA overexpression strain activated the sulfur metabolic pathway in K. xylinus. Due to the insufficient oxygen electron acceptors in the hypoxia, sulfate acted as the final electron acceptor and enhanced the growth ability of the strain. Through global regulation of the pathways of bacterial growth and metabolism as well as BC synthesis under low oxygen conditions, the arcA gene has enabled the strain to reach new levels of BC production. This study lays the foundation for further investigation of the mechanism of the effect of oxygen on BC synthesis in K. xylinus. K. xylinus/ pseva331-FNR, K. xylinus/ pseva331-Arca and K. xylinus/pSEVA331 were cultured in static culture at 15%, 21% and 40% oxygen partial pressures and sequenced by Illumina high-throughput sequencing technology