ROS Is a Factor Regulating the Increased Polysaccharide Production by Light Quality in the Edible Cyanobacterium Nostoc flagelliforme

• Published in: Journal of agricultural and food chemistry Vol. 67; no. 8; pp. 2235 - 2244
• Main Authors: Han, Pei-pei, Shen, Shi-gang, Guo, Rong-jun, Zhao, Dong-xue, Lin, Ya-Hui, Jia, Shi-ru, Yan, Rong-rong, Wu, Yi-kai
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 27.02.2019
• Subjects: Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Culture Media - metabolism; Hydrogen Peroxide - metabolism; Light; Nostoc - genetics; Nostoc - growth & development; Nostoc - metabolism; Nostoc - radiation effects; Oxidation-Reduction; Oxidative Stress - radiation effects; Polysaccharides, Bacterial - biosynthesis; Reactive Oxygen Species - metabolism; polysaccharides; transcriptomics; light quality; Nostoc flagelliforme; ROS
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/acs.jafc.8b06176

To explore the regulatory factor of light quality affecting exopolysaccharide (EPS) production, transcriptome analysis of Nostoc flagelliforme cells exposed to red light (R), blue light (B), and mixed light (B/R = 15:7) (BR) with white fluorescent light as control was performed. The differentially expressed genes mainly enriched in carbohydrate metabolism and energy metabolism. Significant enrichment in the oxidation–reduction process and energy metabolism indicated that intracellular redox homeostasis was disrupted. An assay of reactive oxygen species (ROS) and malondialdehyde contents demonstrated light quality induced oxidative stress. To illustrate the relationship between ROS level and EPS accumulation, the effects of the exogenous addition of ROS scavenger N-acetyl cysteine and inducer H2O2 on the oxidation–reduction level and EPS production were compared. The results revealed that light quality regulated EPS biosynthesis via the intracellular ROS level directly other than oxidative stress. Understanding such relationships might provide guidance for efficient EPS production to regulate the intracellular redox level.