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.

中文翻译：

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通过使用必需的生物合成基因的破坏物作为指示菌株，发现潜在的链霉菌激素生产者。

自动调节剂是控制放线菌中许多次级代谢产物产生的低分子量信号传导化合物，被称为“链霉菌激素”。在这里，在40个链霉菌和11个内生放线菌中研究了链霉菌激素的潜在生产者。分别使用淡紫色链霉菌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（阿维洛利）链霉菌激素的产生。在这些菌株中，链霉菌激素的基本生物合成基因被破坏，使它们仅能对外部添加的激素作出反应。结果表明，每个调查菌株中有20％产生了IM-2和VB，证实γ-丁内酯型链霉菌激素是放线菌中最常见的激素。与γ-丁内酯类型不同，近年来已发现丁烯内酯型链霉菌激素，但其分布尚不清楚。我们的发现，放线菌中有24％（51个菌株中的12个）表现出阿维奈德活性，这首次表明丁烯内酯型链霉菌激素在放线菌中也很常见。