氨基酸对禾粟链霉菌生物合成ε-聚赖氨酸的影响

摘要

Effects of sixteen am ino acids on the ε-polylysine(ε-PL )production by Streptom yces gram ineanis L S-B l were studied using glucose as carbon source . Results showed that ε-PL yield was increased by adding phenylalanine (Phe) , argnine (Arg ) , tyrosine( Tyr) , glycine(G ly ) , asparagine (A sn ) , trpptophane (T ry ) , respectively . The enhancem ent of ε-P L production through addition of Phe was obvious . When 3 mm ol/L Phe was added at the beginning of ferm entation , ε-PL yield was increased by 20％-30％ , reaching 0.488 g/L . The metabolic flux analysis (M FA )of S . gram inearus LS-B1 indicated that metabolic flux distnbution of ε-PL ferm entation was changed by adding Phe . The flux of phosphoenolpyruvate (PEP) to shrkin ate pathw ay w as inhlbited , w hile the fux to ε-PL was increased .%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3 mmol/L时效果最佳,使产量提高了20%～30%,达到0.488 g/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.