Microbial hormones in Streptomyces coelicolor A3 (2)

链霉菌是革兰氏阳性土壤细菌，其特征是能够产生多种有用的次生代谢产物，以及其复杂的生活史，包括气生菌丝和孢子的形成。已知这两种特征表型相互关联，在一些链霉菌中发现了称为伽马丁内酯自体调节剂的低分子化合物来调节这两种表型。然而，在天蓝色链霉菌A3(2)中，遗传研究最多的是天蓝色链霉菌A3(2)，关于调节抗生素生产或形态分化的内在激素的性质尚不清楚。对天蓝色链霉菌A3(2)是否含有调节抗生素产生或形态分化的低分子化合物进行了深入研究。天蓝色链霉菌A3(2)含有一种名为Scb1的化合物，可诱导产生放线菌素和十一烷基灵芝菌素两种抗生素。从500升发酵液中提纯Scb1纯品320杯。通过600 MHz氢谱和MS分析确定了Scb1的平坦结构。建立了四种可能的Scb1立体异构体的手性合成路线，并将天然Scb1与四种合成的异构体进行比较，确定了Scb1As(2R，3R，1‘R)-2-(1’-hydroxy-6‘-methylheptyl)-3-hydroxymethyl)的伽马丁内酯。

Streptomycetes are Gram-positive soil bacteria characterized by their ability to produce numerous kinds of useful secondary metabolites as well as by their complex life cycle including the formation of aerial mycelia and spores. The two characteristic phenotypes have been know to link each other, and low-molecular-weight compounds called gamma-butyrolactone autoregulators have been found in some Streptomyces species to regulate the two phenotypes. However, with the most genetically studied among Streptomyces species, Streptomyces coelicolor A3(2), nothing has been know on the nature of the intrinsic hormones to regulate the antibiotic production or morphological differentiation.1. S.coelicolor A3(2) was studied intensively whether it has low-molecular-weight compounds to regulate the antibiotic production or the morphological differentiation.2. S.coelicolor A3(2) was found to have a compound named Scb1 which induces the production of two antibiotics, actinorhodin and undecylprodigiosin.3. From 500-liters culture broth, 320 mug of pure Scb1 was purified.4. Plain structure of Scb1 was estimated from 600 MHz H-NMR and MS analyses.5. Chiral synthetic routes for four possible Scb1 stereoisomers were established, and comparison of natural Scb1 with the four synthetic isomers resulted in the determination of Scb1 as (2R, 3R, 1'R)-2-(1'-hydroxy-6'-methylheptyl)-3-hydroxymethyl gamma-butanolide.