【摘要】 为了探索氨基酸对Streptomyces graminearus LS-B1以葡萄糖发酵生产ε-聚赖氨酸(ε-PL)的影响,分别在发酵过程中添加了16种常见氨基酸。研究结果表明,苯丙氨酸(Phe)、精氨酸(Arg)、酪氨酸(Tyr)、甘氨酸(Gly)、天冬酰胺(Asn)、色氨酸(Try)6种氨基酸对ε-PL合成有一定的促进作用,其中在发酵初始添加Phe且添加浓度为3mmol/L时效果最佳,使产量提高了20%～30%,达到0.488g/L。代谢流量分析(MFA)显示,添加Phe改变了ε-PL合成的代谢流量分布,抑制了磷酸烯醇式丙酮酸(PEP)向莽草酸途径的通量,从而使其更多的流向了ε-PL合成途径。更多还原

【Abstract】 Effects of sixteen amino acids on the ε-polylysine(ε-PL)production by Streptomyces graminearus LS-B1 were studied using glucose as carbon source.Results showed that ε-PL yield was increased by adding phenylalanine(Phe),argnine (Arg),tyrosine(Tyr),glycine(Gly),asparagine(Asn),tryptophane(Try),respectively.The enhancement of ε-PL production through addition of Phe was obvious.When 3 mmol/L Phe was added at the beginning of fermentation,ε-PL yield was increased by 20%-30%,reaching 0.488 g/L.The metabolic flux analysis(MFA)of S.graminearus LS-B1 indicated that metabolic flux distribution of ε-PL fermentation was changed by adding Phe.The flux of phosphoenolpyruvate (PEP)to shikimate pathway was inhibited,while the flux to ε-PL was increased.更多还原