Biosynthesis of the macrolide antibiotic chlorothricin.
Biosynthesis of the macrolide antibiotic chlorothricin.
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DOI：
10.1021/bi00507a042
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发表时间：
1981-02
期刊：
影响因子：
2.9
通讯作者：
O. Mascaretti;C. Chang;D. Hook;H. Otsuka;E. Kreutzer;H. Floss
中科院分区：
文献类型：
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作者：
O. Mascaretti;C. Chang;D. Hook;H. Otsuka;E. Kreutzer;H. Floss
用13C标记的前体进行饲养实验，并对抗生素及其糖基进行13C NMR分析，建立了抗菌链霉菌代谢产物氯霉素的聚酮生物合成模式。酰基部分是一个取代的6-甲基水杨酸，由四个乙酸单位和一个甲基蛋氨酸衍生而来。糖醛酸由十个乙酸酯和两个丙酸酯单元组成，剩下三个碳原子，C-22， -23和-24，下落不明。两个2-脱氧-d鼠李糖部分来源于葡萄糖，保留了C-1、C-2和C-6上的氢，失去了H-3和H-5。葡萄糖C-4上的氢在分子内转移到己糖的C-6上，以倒置方式取代C-6上的羟基，这一结果暗示了在这种转化中胸苷5 '-二磷酸-葡萄糖氧化还原酶反应。
Feeding experiments with 13C-labeled precursors followed by 13C NMR analysis of the antibiotic and its aglycon have established a polyketide mode of biosynthesis for chlorothricin, a metabolite of Streptomyces antibioticus. The acyl moiety is a substituted 6-methylsalicylic acid derived from four acetate units and a methyl group of methionine. The aglycon is comprised of ten acetate and two propionate units, leaving three carbon atoms, C-22, -23, and -24, unaccounted for. The two 2-deoxy-D-rhamnose moieties are derived from glucose with retention of the hydrogens at C-1, C-2, and C-6 and loss of H-3 and H-5. The hydrogen at C-4 of glucose is transferred intramolecularly to C-6 of the hexose, replacing the hydroxyl group at C-6 in an inversion mode, a result which implicates the thymidine 5'-diphosphate-glucose oxidoreductase reaction in this transformation.