铜绿假单胞菌降解菲的产物鉴定及代谢过程

研究了1株能快速降解疏水性化合物的铜绿假单胞菌NY3对菲的降解机理。GC-MS分析表明,该菌代谢菲的各个阶段,能够被检测到的主要酸性产物有1-羟基-2-萘甲酸、α-萘酚、邻羟基苯基羰基乙酸、水杨酸、苯甲酸等。铜绿假单胞菌NY3经过一系列氧化代谢将菲转化为1-羟基-2-萘甲酸,进一步反应生成α-萘酚。由菲到1-羟基-2-萘甲酸,未检测到其他产物,说明该阶段产物被继续代谢的速度快,产物含量低不易积累。1-羟基-2-萘甲酸为体系中积累的唯一的主要代谢产物。尽管继续代谢速度慢,但它可以按照α-萘酚、邻羟基苯基羰基乙酸、水杨酸、苯甲酸途径被继续转化。NY3降解菲的代谢产物中未检测到二羟基萘、苯二酚等多羟基化合物,但羟基和羧基处于邻位的化合物,如1-羟基-2-萘甲酸和水杨酸有非常明显积累的趋势,α-萘酚和苯甲酸积累速度次之。

On the acidic metabolite characterization and degradation process of the phenanthrene by Pseudomonas aeruginosa NY3

This paper deals with a study on the acidic metabolite characterization and degradation process of the phenanthrene by means of Pseudomonas aeruginosa NY3.As is known,though there has been a lot of articles published on the study of metabolites,yet little has been reported on the biodegradation pathways of polycyclic aromatic hydrocarbons by pseudomonas aeruginosa.Here in this paper we would like to report the typical acidic metabolites of phenanthrene and its degrading pathway by P.aeruginosa NY3,which can help to metabolize hydrophobic compounds quickly.P.aeruginosa NY3,as a matter of fact,could grow on the phenanthrene well and its metabolites such as α-naphthol,salicylic acid,benzoic acid in regard with its sole carbon source and energy.GC-MS data indicate that it is possible to find five major metabolites of phenanthrene as the bacteria grow.They are 1-hydroxy-2-naphthoic acid,2-hydroxy-2-carboxylic acid,α-naphthol,o-hydroxyphenyl carbonyl acid,salicylic acid,and benzoic acid.Based on the analysis of metabolites,the biodegradation pathway can be deduced.First of all,the phenanthrene can be made transformed into 1-hydroxy-2-naphthoic acid after a series of oxidative metabolism steps by P.aeruginosa NY3,and later into α-naphthol through decarboxylation.Other metabolites that can be transformed from phenanthrene into 1-hydroxy-2-naphthoic acid can be metabolized so fast that it won’t be possible to be found in our experiments,though it would be possible to find one-aromatic-ring metabolites like o-hydroxyphenyl carbonyl acid,salicylic acid,benzoic acid were detected was the evidence of further transformation of α-naphthol.However,it wouldn’t be possible to find dihydroxynaphthalene,dihydroxybenzene and other polyphenols could as the metabolites of phenanthrene by pseudomonas aeruginosa NY3,while there were greater amount of metabolites which can be characterized as ortho-hydroxyl carboxyl compounds,such as 1-hydroxy-2-naphthoic acid and salicylic acid which were easily accumulated.This means that the decarboxylation by NY3 is not an easy step and ortho-hydroxyl carboxyl compound rarely transformed into dihenols.α-naphthol and benzoic acid were also somewhat accumulated.And therefore,o-hydroxyphenyl acetic acid has actually been the first report of this nature.