Liang Bin, Du Xin-Jun, Li Ping, Sun Chan-Chan, Wang Shuo
Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Ministry of Education, Tianjin, China.
Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, Beijing, China.
Front Microbiol. 2018 Jun 28;9:1374. doi: 10.3389/fmicb.2018.01374. eCollection 2018.
YY-1 is widely used in food colorant production in China. Our previous study clearly illustrated the whole-genome data for YY-1 and provided useful insight into evolutionary research and industrial applications. However, the presence of citrinin, which has nephrotoxic, hepatotoxic, and carcinogenic activities, has attracted attention to the safety of products. In an effort to reduce the harmful effects of citrinin in related products, a random mutant of YY-1 with low citrinin production (designated as "winter") was obtained in this study. To analyze the biosynthesis and regulation mechanisms of pigment and citrinin, a transcriptomic analysis of the YY-1 and winter strains was performed. Comparative transcriptomic analysis reveals , the essential gene for citrinin synthesis, showed a low expression level in YY-1 and winter, which suggested there might be isoenzymes in YY-1 that were responsible for the citrinin synthesis during evolution. In addition, changes in transcription factor expression may also influence the network regulating the citrinin synthesis pathway in . Moreover, the yields of pigments produced by the winter mutant were significantly increased. Repressing the central carbon metabolism and improving the acetyl-CoA pool can contribute to a high pigment yield, and enhanced NADPH regeneration can also lead to the metabolic flux of pigment production in . Investigations into the biosynthesis and regulation of citrinin and pigment production in will enhance our knowledge of the mechanisms behind the biosynthesis of fungal secondary metabolites.
YY-1在中国被广泛用于食用色素生产。我们之前的研究清晰地展示了YY-1的全基因组数据，并为进化研究和工业应用提供了有益的见解。然而，桔霉素的存在具有肾毒性、肝毒性和致癌活性，这引起了人们对相关产品安全性的关注。为了降低桔霉素在相关产品中的有害影响，本研究获得了一株桔霉素产量低的YY-1随机突变体（命名为“winter”）。为了分析色素和桔霉素的生物合成及调控机制，对YY-1和winter菌株进行了转录组分析。比较转录组分析显示，桔霉素合成的关键基因在YY-1和winter中表达水平较低，这表明在进化过程中YY-1可能存在负责桔霉素合成的同工酶。此外，转录因子表达的变化也可能影响桔霉素合成途径的调控网络。而且，winter突变体产生的色素产量显著增加。抑制中心碳代谢并改善乙酰辅酶A库有助于提高色素产量，增强NADPH再生也可导致色素产生的代谢通量。对桔霉素和色素生物合成及调控的研究将增进我们对真菌次级代谢产物生物合成机制的了解。
