Aerial mycelium-inducing substances of actinomycetes and their application to the regulation of antibiotic production

我们对放线菌进行了筛选实验，发现放线菌的空中菌丝形成受其培养材料中活性物质的调节，有几种放线菌产生了空中菌丝诱导物质。从白链霉菌IFO 12738中分离得到活性物质pamamycin-607，其结构为一种具有二甲胺基侧链的新型十六元大二内酯。在0.1 ug/碟浓度下，帕霉素607诱导空生菌丝阴性菌株的空生菌丝。用帕霉素-607在苯和水之间分配KMnO_4时，水中没有分配K^+，而MnO_4-从水中转移到苯层；pamaycin-607是一种新型的阴离子转移物质。从双歧杆菌的培养液中纯化出活性物质，经鉴定为Ca(OAc)_2。假设Ca^<2+>来源于CaCO_3， CaCO_3是培养基的一个组成部分，随着双歧杆菌的生长和培养基的酸化而被溶解。Ca^<2+>在1 mM以上诱导双氧菌气生菌丝形成，其作用被Ca^<2+>特异性螯合剂ECTA抑制。对36株放线菌的调查表明，Ca^<2+>对21株放线菌（58%）的气生菌丝形成有调节作用。培养基中形成空中菌丝所需的Ca^<2+>浓度在0.1 ~ 1.5 mM之间。它是水溶性的，不吸附在木炭上。有趣的是，当空气菌丝体被这种化合物诱导时，菌株开始产生抗生素。

As the results of screening experiments on actinomycetes in whcih aerial mycelium formation was regulated by active substances present in their cultured materials, we found that several species produced aerial mycelium-inducing substances. The active substance named pamamycin-607 was isolated from Strepomyces alboniger IFO 12738, and the structure was elucidated as a novel sixteen-membered macrodiolide with dimethylamino group-bearing side chain. At 0.1 ug/disc pamamycin-607 induced aerial mycelia in the aerial mycelium-negative strain. When KMnO_4 was partitioned with pamamycin-607 between benzene and water, MnO_4- but no K^+ was partitioned transferred from the water to the benzene layer; thus pamaycin-607 was shown to be a novel anion-transfer substance. From the culture broth of S. ambofaciens the actice substance was purified and identified as Ca(OAc)_2. It was assumed that the Ca^<2+> was derived from the CaCO_3 which was a component of the medium and had been solubilized as S. ambofaciens grew and acidified the culture medium. Ca^<2+> induced aerial mycelium formation in S. ambofaciens at above 1 mM, and its effect was inhibited by ECTA, a Ca^<2+> specific chelating reagent. A survey of 36 strains of actinomycetes showed that Ca^<2+> regulated aerial mycelium formation in 21 straing (58%) of them. The Ca^<2+> concentration required for aerial mycelium formation in the culture medium ranged from 0.1 to 1.5 mM. We found that S. venezuelae produced the aerial myceliuminducing substance; which was water-soluble and not adsorbed on charcoal. Interestingly, when aerial mycelium was induced by thiscompound, the strain began to produce the antibiotic.