The novel hydroxylation reaction of nicotinic acid catalyzed by the cooperation of yeat and bacteria

各种吡啶衍生物可作为合成各种生理活性化合物的基石。例如，最近研制出了一种新的强效杀虫剂——吡虫啉，属于尼古丁类。这些含尼古丁的杀虫剂因其活性强、毒性低而被广泛使用。然而，传统的化学合成方法很难合成6-氯吡啶基的组成部分。因此，需要开发合成构件的新工艺。为此，我们研究了吡啶环的酶促区域特异性羟基化反应，建立了3-氰吡啶6位特异性羟基化的新工艺。接下来，我们试图分离微生物。催化烟酸的2位羟基化反应。2-羟基烟酸还可以作为合成具有生理活性的化合物的基本成分。然而，通过传统的以烟酸为碳源和/或氮源的富集培养，我们无法分离出催化烟酸2位特异性羟基化的微生物。所有的烟酸降解微生物催化6位特定的烟酸羟基化。因此，我们尝试以6-甲基烟酸作为唯一碳源和/或氮源进行富集培养。经过长时间的富集培养，我们发现混合培养具有6-甲基烟酸2位羟基化活性。混合培养还催化了烟酸的2位特异性羟基化反应。从混合培养液中发现了念珠菌和鞘单胞菌两种微生物。每个菌株不催化烟酸的羟基化。只有当它们一起培养时，才能发现烟酸的2位特异性羟基化。因此，我们发现了念珠菌和鞘氨单胞菌的协同作用。然而，协同羟基化作用的机制目前尚不清楚。少

Various pyridine derivatives are useful as the building block for the synthesis of various physiologically active compounds. For example, recently, the new powerful insecticide, imidachloprid belonging to nicotinly group, has been developed. These nicotinly insecticides are widely used due to its powerful activity and low toxicity. However, it was not easy to synthesize the building block of 6-chloropyridyl through the conventional chemical synthesis. Thus, the development of the new process for the synthesis of the building block was required. To accomplish this purpose, we investigated the enzymatic regio-specific hydroxylation reaction of pyridine ring and we established the new production process of the 6-position specific hydroxylation of 3-cyanopyridine.Next, we attempted to isolate the microorganisms. which catalyze the 2-position specific hydroxylation of nicotinic acid. 2-Hydroxynicotinic acid might be also useful as the building block for the synthesis of phisiological active … More compounds. However, through the conventional enrichment culture using nicotinic acid as carbon and/or nitrogen source, we could not isolate the microorganisms which catalyze the 2-position specific hydroxylation of nicotinic acid. All nicotinic acid-degrading microorganism catalyzes 6-position specific hydroxylation of nicotinic acid. Thus, we attempted the enrichment culture using 6-methylnicotinic acid as sole carbon and/or nitrogen source. After the prolong enrichment culture, we found the mixed culture exhibit the 2-position hydroxylating activity of 6-methylnicotinic acid. The mixed culture also catalyzed the 2-position specific hydroxylation of nicotinic acid. We found two kinds of microorganism, Candida yeast and Sphingomonas bacteria from the mixed culture broth. Each strain does not catalyze the hydroxylation of nicotinic acid. Only when they were cultivated together, 2-position specific hydroxylation of nicotinic acid was found. Thus, we found the cooperative function of Candida yeast and Sphingomonas bacteria. However, the mechanisms of cooperative hydroxylation are not clear now. Less