Abstract Cadaverine, also known as 1,5-diaminopentane, is a biogenic amine particularly used for the synthesis of nylon. Cadaverine can be efficiently synthesized through decarboxylation of lysine in microorganisms. However, the respective metabolic pathways in Escherichia coli results in many byproducts in parallel with cadaverine synthesis via genes such as speE, speG, ygjG, and puuA. In this study, nine different types of deletion strains were constructed from the aforementioned four genes to explore their effects on cadaverine production in a T7 promoter based systemic bicistronic cadA-cadB transformed recombinant E. coli. Results show that all the deletion strains could increase cadaverine productivity compared to the deletion-free strain when the culture was supplemented with l -lysine. The cadaverine production from l -lysine with the deletion strains increased 3 folds when compared with that of the deletion-free strain at the cultivation time of 16 h. This indicates that the deletion strain could successfully facilitate lysine consumption and block the undesirable metabolic pathways.

中文翻译：

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通过基因缺失促进工程大肠杆菌中赖氨酸酶促转化为尸胺

摘要 尸胺又称1,5-二氨基戊烷，是一种生物胺，特别用于尼龙的合成。尸胺可以通过微生物中赖氨酸的脱羧来有效合成。然而，大肠杆菌中各自的代谢途径导致许多副产物与尸胺通过基因如 speE、speG、ygjG 和 puuA 合成并行。在这项研究中，从上述四种基因构建了九种不同类型的缺失菌株，以探索它们对基于 T7 启动子的系统性双顺反子 cadA-cadB 转化重组大肠杆菌中尸胺产生的影响。结果显示，当培养物补充有l-赖氨酸时，所有缺失菌株与无缺失菌株相比都可提高尸胺生产力。在培养 16 小时时，与无缺失菌株相比，带有缺失菌株的 l-赖氨酸的尸胺产量增加了 3 倍。这表明缺失菌株可以成功促进赖氨酸消耗并阻断不良代谢途径。