The interspecies communication roles of γ-butyrolactones (GBLs) have been described for a long time but are still poorly understood. Herein, we analyzed more than 1000 Streptomyces strains and noticed a big quantitative gap between the strains with GBL biosynthetic genes and the strains with GBL receptor genes, which implies the wide-spread of GBLs as interspecies signals in Streptomyces and their great potential in the activation of silent natural product gene clusters. Streptomyces albidoflavus J1074, which has one GBL receptor gene but no GBL biosynthetic gene, was chosen as a target to study the possible interspecies communication roles of GBLs. At first, the GBL biosynthetic genes from Streptomyces coelicolor M145 were expressed in S. albidoflavus J1074, which enabled the S. albidoflavus strains to synthesize Streptomyces coelicolor butanolides (SCBs) and activated the production of paulomycins. Further studies showed that this activation process requires the participation of the GBL receptor gene XNR_4681. The results suggest that the expression of exogenous GBL biosynthetic genes can modulate the metabolisms of GBL non-producing strains, and this regulation role might be meaningful for silent gene cluster activation in Streptomyces. At final, we synthesized racemic-SCB2 and tried to simplify the activation process by adding SCB2 directly to S. albidoflavus J1074, which unfortunately failed to induce paulomycin production.

中文翻译：

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Albidoflavus J1074链霉菌中外源性γ-丁内酯信号分子对paulomycin生产的激活。

γ-丁内酯（GBLs）的种间交流作用已被描述了很长时间，但仍知之甚少。在本文中，我们分析了1000多种链霉菌菌株，发现具有GBL生物合成基因的菌株与具有GBL受体基因的菌株之间存在巨大的定量差距，这表明GBL作为种间信号在链霉菌中的广泛传播及其在激活方面的巨大潜力沉默的天然产物基因簇。选择具有一个GBL受体基因但没有GBL生物合成基因的白色链霉菌J1074作为研究GBLs的种间传播角色的目标。首先，来自天蓝色链霉菌M145的GBL生物合成基因在S. albidoflavus J1074中表达，这使得S. albidoflavus J1074成为可能。albidoflavus菌株可以合成链霉菌coelicolor丁醇化物（SCBs）并激活保罗霉素的生产。进一步的研究表明，这种激活过程需要GBL受体基因XNR_4681的参与。结果表明外源GBL生物合成基因的表达可以调节GBL非生产菌株的代谢，这种调节作用可能对链霉菌中的沉默基因簇激活有意义。最后，我们合成了外消旋-SCB2，并尝试通过将SCB2直接添加到S. albidoflavus J1074中来简化激活过程，不幸的是，该菌株未能诱导生成保罗霉素。结果表明外源GBL生物合成基因的表达可以调节GBL非生产菌株的代谢，这种调节作用可能对链霉菌中的沉默基因簇激活有意义。最后，我们合成了外消旋-SCB2，并尝试通过将SCB2直接添加到S. albidoflavus J1074中来简化激活过程，不幸的是，该菌株未能诱导生成保罗霉素。结果表明外源GBL生物合成基因的表达可以调节GBL非生产菌株的代谢，这种调节作用可能对链霉菌中的沉默基因簇激活有意义。最后，我们合成了外消旋-SCB2，并尝试通过将SCB2直接添加到S. albidoflavus J1074中来简化激活过程，不幸的是，该菌株未能诱导生成保罗霉素。