Maretzki, Andrew (Pennsylvania State University, University Park) and M. F. Mallette. Nutritional factors stimulating the formation of lysine decarboxylase in Escherichia coli. J. Bacteriol. >83:720–726. 1962 — Inclusion of complex nitrogen sources in the induction medium was shown to be necessary for the synthesis of appreciable amounts of l-lysine decarboxylase by Escherichia coli B. Hy-case, a commercial acid hydrolyzate of casein, was especially effective in enzyme production, which was assayed manometrically after lysis of the bacteria from without by bacteriophage. Partial fractionation of the Hy-case, identification of the free amino acids, and addition of these amino acids to test media revealed stimulatory effects by methionine, threonine, proline, leucine, and tyrosine. A full complement of amino acids did not match the enzyme levels reached in the presence of Hy-case. Certain peptide fractions obtained from this mixture supplemented the effects of the amino acids in such a way as to suggest direct incorporation of peptide rather than transport or protective roles. Added purines, pyrimidines, iron, and water-soluble vitamins were without effect. Neither carbohydrates nor phosphorylated materials could be detected in the stimulatory fractions.
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机译：Maretzki，Andrew（宾夕法尼亚州立大学，大学公园分校）和M. F. Mallette。营养因素刺激大肠杆菌中赖氨酸脱羧酶的形成。 J.细菌。 > 83： 720-726。 1962年—在诱导培养基中包含复杂的氮源对于通过大肠杆菌B合成相当数量的l-赖氨酸脱羧酶是必要的。酪蛋白的商业酸性水解产物Hy-case在生产酶方面特别有效，在不使用噬菌体溶解细菌后，对其进行了压力测定。 Hy-case的部分分级分离，游离氨基酸的鉴定以及将这些氨基酸添加到测试培养基中显示，甲硫氨酸，苏氨酸，脯氨酸，亮氨酸和酪氨酸具有刺激作用。完整的氨基酸补体与在Hy-case存在下达到的酶水平不匹配。从该混合物中获得的某些肽级分以暗示肽直接掺入而不是转运或保护性作用的方式补充了氨基酸的作用。添加嘌呤，嘧啶，铁和水溶性维生素无效。在刺激部分中均未检测到碳水化合物或磷酸化物质。
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