Comamonas sp. IDO2合成靛蓝的特性研究

利用吲哚降解菌丛毛单胞菌(Comamonas)IDO2转化吲哚合成靛蓝,优化靛蓝合成条件,并对合成产物进行分析.结果表明,菌株IDO2能够在苯酚、萘、苯和菲的诱导下转化吲哚合成靛蓝,在苯酚诱导时靛蓝的产量最高.采用表面响应法优化菌株合成靛蓝的条件:吲哚197.76mg·L~(-1),苯酚203.39 mg·L~(-1),酵母浸粉0.18%,在此条件下靛蓝的合成量为9.0 mg·L~(-1),与初始条件下的产量相比提高了104%.此外,考察了不同金属离子对菌株IDO2合成靛蓝的影响,结果表明Ba~(2+)和Ca~(2+)对靛蓝的合成具有促进作用.采用液相色谱/飞行时间/质谱联用对菌株IDO2转化吲哚的产物进行定量和定性分析,发现合成产物主要为靛蓝和靛红,并依此提出了可能的反应途径.

Characteristics of indigo biosynthesis by Comamonas sp. IDO2

The indole-degrading strain Comamonas sp. IDO2 was able to produce indigo from indole. The variables in indigo production were optimized, and the metabolites during the biotransformation were analyzed. The results showed that strain IDO2 could produce indigo by utilizing phenol, naphthalene, benzene and phenanthrene as the inducers, and the highest yield of indigo was obtained with phenol as the inducer. The optimal conditions for indigo production were determined using response surface methodology (RSM) as follows:indole 197.76 mg·L^-1, phenol 203.39 mg·L^-1 and yeast extracts 0.18%, and 9.0 mg·L^-1 indigo was produced by strain IDO2, which increased 104% compared with that produced under initial conditions. In addition, the effects of metal ions on indigo production were investigated, which indicated that Ba²⁺ and Ca²⁺ could promote the biotransformation of indole to indigo by strain IDO2. Liquid chromatography/time-of-flight/mass spectrometry (LC/TOF/MS) was applied to analyze the metabolites during the biotransformation, and both indigo and isatin were detected. Accordingly, the possible pathway for indigo production from indole by strain IDO2 was proposed.