Thao Nguyen B, Kitani Shigeru, Nitta Hiroko, Tomioka Toshiya, Nihira Takuya
International Center for Biotechnology, Osaka University, Osaka, Japan.
Faculty of Science, MU-OU Collaborative Research Center for Bioscience and Biotechnology, Mahidol University, Bangkok, Thailand.
J Antibiot (Tokyo). 2017 Oct;70(10):1004-1008. doi: 10.1038/ja.2017.85. Epub 2017 Jul 19.
Autoregulators are low-molecular-weight signaling compounds that control the production of many secondary metabolites in actinomycetes and have been referred to as 'Streptomyces hormones'. Here, potential producers of Streptomyces hormones were investigated in 40 Streptomyces and 11 endophytic actinomycetes. Production of γ-butyrolactone-type (IM-2, VB) and butenolide-type (avenolide) Streptomyces hormones was screened using Streptomyces lavendulae FRI-5 (ΔfarX), Streptomyces virginiae (ΔbarX) and Streptomyces avermitilis (Δaco), respectively. In these strains, essential biosynthetic genes for Streptomyces hormones were disrupted, enabling them to respond solely to the externally added hormones. The results showed that 20% of each of the investigated strains produced IM-2 and VB, confirming that γ-butyrolactone-type Streptomyces hormones are the most common in actinomycetes. Unlike the γ-butyrolactone type, butenolide-type Streptomyces hormones have been discovered in recent years, but their distribution has been unclear. Our finding that 24% of actinomycetes (12 of 51 strains) showed avenolide activity revealed for the first time that the butenolide-type Streptomyces hormone is also common in actinomycetes.
自体调节因子是低分子量信号化合物，可控制放线菌中许多次级代谢产物的产生，被称为“链霉菌激素”。在此，对40株链霉菌和11株内生放线菌中链霉菌激素的潜在产生菌进行了研究。分别使用薰衣草链霉菌FRI-5（ΔfarX）、弗吉尼亚链霉菌（ΔbarX）和阿维链霉菌（Δaco）筛选γ-丁内酯型（IM-2、VB）和丁烯内酯型（燕麦内酯）链霉菌激素的产生情况。在这些菌株中，链霉菌激素的必需生物合成基因被破坏，使其仅对外源添加的激素作出反应。结果表明，所研究的每种菌株中有20%产生IM-2和VB，证实γ-丁内酯型链霉菌激素在放线菌中最为常见。与γ-丁内酯型不同，丁烯内酯型链霉菌激素近年来才被发现，但其分布情况尚不清楚。我们发现24%的放线菌（51株中的12株）具有燕麦内酯活性，首次揭示丁烯内酯型链霉菌激素在放线菌中也很常见。
