Biosynthesis of Phenazine Antibiotics in <i>Streptomyces antibioticus</i>: Stereochemistry of Methyl Transfer from Carbon-2 of Acetate
作者:Matthew McDonald、Barrie Wilkinson、Clinton W. Van't Land、Ulla Mocek、Sungsook Lee、Heinz G. Floss
DOI:10.1021/ja991159i
日期:1999.6.1
Stable isotope labeling experiments have shown that the biosynthesis of the monomeric phenazines, the saphenyl esters, and their dimerization products, the esmeraldins, in Streptomyces antibioticus Tu 2706 proceeds from phenazine-1,6-dicarboxylic acid by chain extension with C-2 of acetate to 6-acetylphenazine-1-carboxylic acid, which is reduced to saphenic acid. The latter is incorporated into both
稳定同位素标记实验表明,在抗生素链霉菌 Tu 2706 中,单体吩嗪、苯酯及其二聚化产物 esmeraldins 的生物合成是从吩嗪-1,6-二羧酸通过与乙酸的 C-2 进行链延伸进行的到 6-乙酰吩嗪-1-羧酸,后者被还原为隐苯酸。后者被纳入 esmeraldins 的两半,尽管有所不同。通过加入手性乙酸盐、降解生成的苯酯和 esmeraldins 以及对形成的乙酸进行构型分析,发现链延长过程是在甲基的构型发生整体反转的情况下进行的。这表明假设中间体 β-酮酸的脱羧以反转模式进行。