Microbial mineralization of ring-substituted anilines through an ortho-cleavage pathway
Microbial mineralization of ring-substituted anilines through an ortho-cleavage pathway
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DOI：
10.1128/aem.50.2.447-453.1985
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发表时间：
1985-08
影响因子：
4.4
通讯作者：
J. Zeyer;A. Wasserfallen;K. Timmis
中科院分区：
文献类型：
--
作者：
J. Zeyer;A. Wasserfallen;K. Timmis
莫拉氏菌属菌株G能够利用苯胺、4-氟苯胺、2-氯苯胺、3-氯苯胺、4-氯苯胺（PCA）和4-溴苯胺作为碳和氮的唯一来源，但不能利用4-碘苯胺、4-甲基苯胺、4-甲氧基苯胺或3，4-二氯苯胺。在PCA上的世代时间为6 h。通过对降解中间产物和酶活性的分析，研究了五氯苯甲醚的降解途径。分离菌株G的突变体以增强特定途径中间体的积累。PCA被苯胺加氧酶转化为4-氯儿茶酚，其又通过修改的邻位裂解途径降解。苯胺加氧酶的合成可被多种苯胺诱导。该酶具有广泛的底物特异性。其对取代苯胺的比活性似乎与取代基的尺寸比与吸电子效应更相关，并且对于具有大于碘或甲基的取代基的苯胺非常低。邻位裂解途径的起始酶邻苯二酚1，2-双加氧酶具有与氯苯甲酸和氯苯酚降解途径的相应酶相似的特性，即对氯代和甲基化邻苯二酚具有广泛的底物特异性和高活性。
Moraxella sp. strain G is able to utilize as sole source of carbon and nitrogen aniline, 4-fluoroaniline, 2-chloroaniline, 3-chloroaniline, 4-chloroaniline (PCA), and 4-bromoaniline but not 4-iodoaniline, 4-methylaniline, 4-methoxyaniline, or 3,4-dichloroaniline. The generation time on PCA was 6 h. The pathway for the degradation of PCA was investigated by analysis of catabolic intermediates and enzyme activities. Mutants of strain G were isolated to enhance the accumulation of specific pathway intermediates. PCA was converted by an aniline oxygenase to 4-chlorocatechol, which in turn was degraded via a modified ortho-cleavage pathway. Synthesis of the aniline oxygenase was inducible by various anilines. This enzyme exhibited a broad substrate specificity. Its specific activity towards substituted anilines seemed to be correlated more with the size than with the electron-withdrawing effect of the substituent and was very low towards anilines having substituents larger than iodine or a methyl group. The initial enzyme of the modified ortho-cleavage pathway, catechol 1,2-dioxygenase, had similar characteristics to those of corresponding enzymes of pathways for the degradation of chlorobenzoic acid and chlorophenol, that is, a broad substrate specificity and high activity towards chlorinated and methylated catechols.