不同系统pJP4质粒介导基因强化降解2,4-D效应研究  

Plasmid pJP4 Mediated Gene-augmentation in Different Systems and Its Effect on 2,4-D Biodegradation

作　　者：全向春[1] 汤华[1] 王育来[1] 何孟常[1] 

机构地区：[1]北京师范大学环境学院,水环境模拟国家重点实验室,北京100875

出　　处：《环境科学》2009年第7期2099-2104,共6页Environmental Science

基　　金：国家自然科学基金项目(50508006);国家重点基础研究发展规划(973)项目(2004CB418502)

摘　　要：以携带pJP4质粒的基因工程菌Pseudomonas putida SM1443∷gfp2x(pJP4∷dsRed)为供体菌,考察了pJP4质粒在4种纯菌中的转移效应;并分别针对活性污泥、生物膜、颗粒污泥和河流沉积物系统,通过实验室小试实验考察了该基因工程菌对不同系统目标污染物2,4-二氯苯氧乙酸(2,4-D)的强化降解效应.结果表明,该基因工程菌中的pJP4质粒能够以广泛的微生物细胞为受体菌发生水平转移;向活性污泥、生物膜、颗粒污泥和河流沉积物系统加入一定量的基因工程菌,对2,4-D的降解都能够产生明显的促进作用.对于活性污泥系统(2,4-D初始浓度为450mg/L),强化与对照系统反应143.5h时2,4-D去除率分别为66%和54%;对于生物膜系统(2,4-D初始浓度为180mg/L),强化与对照系统在反应113h时对其去除率分别为99%和61%;对于颗粒污泥系统(2,4-D初始浓度为160mg/L),强化系统2,4-D在62h接近完全去除,而对照系统66h去除率仅为26%;对于沉积物系统(2,4-D初始浓度为2mg/L),强化与对照系统344h去除率分别为93%和69%.激光共聚集扫描显微(CLSM)分析揭示并证实了不同基因强化系统接合子的形成与存在.With pJP4 plasmid carrying genetic engineering bacteria Pseudomonas putida SM1443∷gfp2x （pJP4∷dsRed） as the donor, horizontal gene transfer of pJP4 plasmid in 4 isolated pure strains was investigated, and effects of the donor bacteria inoculation on the removal of the target pollutant 2,4-dichlorophenoxyacetic acid （2,4-D） was studied through conducting gene augmentation in activated sludge, biofilm, aerobic granular sludge and river sediment system, respectively. Results showed that plasmid pJP4 could transfer from Pseudomonas putida SM1443 to a broad spectrum of bacteria. Inoculation of pJP4 plasmid carrying donor bacterium apparently promoted the degradation of 2,4-D for all the above four systems. For the activated sludge system （2,4-D initial concentration at 450 mg/L）, 66 % and 54 % removal of 2,4-D was achieved after 143.5 h reaction for the gene augmented and control system, respectively. For the biofilm system with 2,4-D initial concentration at 180 mg/L, 2,4-D removal percentage at 113 h was 99 % and 61%, respectively. For aerobic granular sludge system（2,4-D initial concentration at 160 mg/L）, 2,4-D was nearly completely removed by 62 h in the gene-angmented system, while the control system only degraded 26 % at 66 h. For the system with sediment （2,4-D initial concentration at 2 mg/L）, 93 % and 69 % removal of 2,4-D was obtained at 344 h reaction for the gene augmented and control system, respectively. Confocal laser scanning microscopy （CLSM） analysis revealed the formation and presence of transconjugants in different gene augmentation systems.

关 键 词：基因强化 2 4-D 接合子 生物降解 基因水平转移 

分 类 号：X172[环境科学与工程—环境科学]