Aureothin and neoaureothin (spectinabilin) represent rare nitroaryl-substituted polyketide metabolites from Streptomyces thioluteus and Streptomyces orinoci, respectively, which only differ in the lengths of the polyene backbones. Cloning and sequencing of the 39 kb neoaureothin (nor) biosynthesis gene cluster and its comparison with the aureothin (aur) pathway genes revealed that both polyketide synthase (PKS) assembly lines are remarkably similar. In both cases the module architecture breaks with the principle of colinearity, as individual PKS modules are used in an iterative fashion. Parsimony and neighbour-joining phylogenetic studies provided insights into the evolutionary process that led to the programming of these unusual type I PKS systems and to prediction of which modules act iteratively. The iterative function of the first module in the neoaureothin pathway, NorA, was confirmed by a successful cross-complementation.

中文翻译：

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非共线聚酮化合物在金黄色素和新金黄色素途径中的生物合成：进化的观点。

Aureothin和新Aureothin（spectinabilin）分别代表来自硫链霉菌和链霉菌的稀有硝基芳基取代的聚酮化合物代谢物，仅在多烯骨架的长度上有所不同。39 kb的新aureothin（nor）生物合成基因簇的克隆和测序以及与aureothin（aur）途径基因的比较表明，两个聚酮化合物合酶（PKS）装配线都非常相似。在这两种情况下，模块架构都违反了共线性原理，因为单个PKS模块以迭代方式使用。简约和邻近的系统发育研究为进化过程提供了见识，这些进化过程导致对这些异常的I型I PKS系统进行编程，并预测了哪些模块可以迭代地起作用。