Toluene and ethylbenzene oxidation by purified naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4
Toluene and ethylbenzene oxidation by purified naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4
复制标题
DOI：
10.1128/aem.62.9.3101-3106.1996
复制
发表时间：
1996-09
影响因子：
4.4
通讯作者：
Kyoung Lee;David T. Gibson
中科院分区：
文献类型：
--
作者：
Kyoung Lee;David T. Gibson
从假单胞菌中分离纯化萘双加氧酶(NDO)。菌株NCIB 9816-4分别通过苄基单氧化和依赖二氧的醇氧化反应将甲苯氧化为苯甲醇和苯甲醛。二甲苯和硝基甲苯的异构体也被氧化成取代苯甲醇和苯甲醛的衍生物。NDO依次通过(S)-1-苯乙醇(77%对映体过量)和苯乙酮氧化乙苯生成2-羟基苯乙酮。此外，NDO还通过脱饱和反应和二羟化反应将乙苯通过苯乙烯氧化成(R)-1-苯基-1，2-乙二醇(对映体过量为74%)。18O2、H218O和D2O的同位素实验表明，1-苯乙醇通过减饱和和互变异构化的微小反应被氧化为苯乙酮。在1-苯乙醇和苯甲醇分别转化为苯乙酮和苯甲醛的主要反应中，可能涉及单羟基化生成宝石二醇中间体，该中间体立体地失去进入的羟基离开羰基产物。这些结果与细胞色素P-450催化的类似反应进行了比较。
Purified naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 oxidized toluene to benzyl alcohol and benzaldehyde by reactions involving benzylic monooxygenation and dioxygen-dependent alcohol oxidation, respectively. Xylene and nitrotoluene isomers were also oxidized to substituted benzyl alcohol and benzaldehyde derivatives. NDO oxidized ethylbenzene sequentially through (S)-1-phenethyl alcohol (77% enantiomeric excess) and acetophenone to 2-hydroxyacetophenone. In addition, NDO also oxidized ethylbenzene through styrene to (R)-1-phenyl-1,2-ethanediol (74% enantiomeric excess) by reactions involving desaturation and dihydroxylation, respectively. Isotope experiments with 18O2, H2 18O, and D2O suggest that 1-phenethyl alcohol is oxidized to acetophenone by a minor reaction involving desaturation followed by tautomerization. The major reaction in the conversion of 1-phenethyl alcohol and benzyl alcohol to acetophenone and benzaldehyde, respectively, probably involves monohydroxylation to form a gem-diol intermediate which stereospecifically loses the incoming hydroxyl group to leave the carbonyl product. These results are compared with similar reactions catalyzed by cytochrome P-450.