[一种拟除虫菊酯降解菌的分离、鉴定及降解基因克隆]

[Isolation, identification and degrading gene cloning of a pyrethroids-degrading bacterium].

作者信息

Zhang Songbai, Zhang Deyong, Liu Yong, Luo Xiangwen, Cheng Feixue, Luo Yuanhua

机构信息

Branch of Longping, Graduate College, Central South University, Changsha 410125, China.

出版信息

Wei Sheng Wu Xue Bao. 2009 Nov;49(11):1520-6.

PMID:20112682

Abstract

OBJECTIVE

This study aimed to isolate, identify and clone degrading gene of a synthetic pyrethroids degrading bacterium.

METHODS

A photosynthetic bacterial strain PSB07-21 capable of degrading several synthetic pyrethroids efficiently was isolated by an enrichment culture. PSB07-21 was identified based on its morphology, physiology and phylogenetic analysis of 16S rDNA sequence. The degradation ability of this strain was evaluated with gas chromatography.The degrading gene was cloned with PCR.

RESULTS

PSB07-21 was closely related to Rhodopseudomonas sp. The optimum condition of degrading synthetic pyrethroidss was at 35 degrees C, pH 7 and 3000 lx. PSB07-21 could degrade fenpropathrin, cypermethrin and bipthenthrin by 66.63%, 43.25% and 50.18% in a concentration of 600 mg/L at day 15, respectively. We cloned a putative gene which was 326bp long with 37.0% identical to 20G-Fe (II) oxygenase gene. When compensating low concentration Fe (II) in PSB medium with synthetic pyrethroids, the degradation efficiency of PSB07-21 was enhanced.

CONCLUSION

The strain has the potential application to synthetic pyrethroids bioremediation.

摘要

目的

本研究旨在分离、鉴定和克隆一种合成拟除虫菊酯降解菌的降解基因。

方法

通过富集培养分离出一株能高效降解多种合成拟除虫菊酯的光合细菌菌株PSB07 - 21。基于其形态、生理特征及16S rDNA序列的系统发育分析对PSB07 - 21进行鉴定。用气相色谱法评估该菌株的降解能力。通过PCR克隆降解基因。

结果

PSB07 - 21与红假单胞菌属密切相关。降解合成拟除虫菊酯的最佳条件为35℃、pH 7和3000勒克斯。在第15天，PSB07 - 21在600 mg/L浓度下对甲氰菊酯、氯氰菊酯和联苯菊酯的降解率分别为66.63%、43.25%和50.18%。我们克隆了一个推定基因，其长度为326bp，与20G - Fe（II）加氧酶基因的同源性为37.0%。用合成拟除虫菊酯补偿PSB培养基中低浓度的Fe（II）时，PSB07 - 21的降解效率提高。