金属离子对红霉素合成及组分转化的影响及机理分析

摘要

Objective To study effects and mechanism analysis of Co2+,Zn2+ and Na2MoO4 on biosynthesis and component transformation of erythromycin by Streptomyces erythraea.Methods The optimal ratio of metal ions was obtained through shake flask experiments,and the culture process was performed in 15L fermentation tank successfully.At the same time,the expression of hydroxylation gene eryK and methylation gene eryG were also studied in shake flask of Streptomyces erythraea.Results The final titer was improved from 8433U/mL(control) to 11858U/mL,and the relative percentage of erythromycin A increased from 83.6％ to 89％ in 15L fermentation tank using the optimal combination of metal ions in shake flask.The addition of metal ions can improve the gene expression of eryK and eryG.Further more,the radio of eryK/eryG had a relatively close relationship with the components of erythromycin.Conclusion It was suggested that stimulating the transcription of related genes by metal ions may play an important role in the biosynthesis and component transformation of erythromycin.%目的 研究Co2+、Zn2+和Na2MoO4 3种金属离子对糖多孢红霉菌发酵生产红霉素及组分转化的影响,并对其影响机理进行相关分析.方法 通过摇瓶实验确定金属离子最优配比,并在15L发酵罐上放大;通过菌体在合成培养基中的摇瓶发酵研究红霉素合成途径中羟基化基因eryK、甲基化基因eryG的表达量与红霉素合成及组分转化的关系.结果 3种金属离子的添加使红霉素发酵单位由对照罐8433U/mL提高到11858U/mL,有效组分ErA由对照83.6％提高到89％;ery和eryG两种基因的表达量显著提高,且eryK/eryG比值与有效组分ErA含量具有较好的相关性.结论 3种金属离子能通过调节菌种相关基因的表达,对红霉素的合成及组分转化产生促进作用.