4株多环芳烃降解菌的分离及鉴定

以多环芳烃(PAHs)为筛选培养基,从石油污染土壤和石油废水中筛选到4株能够降解PAHs的高效微生物菌株,分别定名为3-28、NF、EW和EY;并对其进行了形态学观察、生理生化指标测定及分子生物学鉴定.16S rDNA序列分析显示,这4株细菌分别有581、582、1209和1230个碱基,与Microbacterium、Cellulosimicrobium、Chelatococcus和Sphingopyxis等4个属有较高的序列同源性,分别为100%、97.8%、98.2%和99.0%.结合表型特征和16S rDNA序列分析,用DNAMAN构建系统发育树,并用Bootstraping法对其评价,初步将3-28、NF、EW和EY这4株PAHs降解菌分别归属于Microbacterium sp.、Cellulosimicrobium sp.、Chelatococcus sp.和Sphingopyxis sp..图3表1参22

Screening and Identification of Four PAHs-biodegrading Strains

Microbes play an important role in bio-remediation technologies, and it is a basic study to find out effectively functional strains for environmental bio-remediation. In this paper four PAHs-biodegrading strains were screened with a selective medium of PAHs from oily wastewater and oil-contaminated soil. The four strains were identified by their morphological, physiological and biochemical characteristics and gene analyses, and they were named as 3-28, NF, EW and EY. The 16S rDNA of the strains was amplified by PCR, indicating that they possessed 581, 582, 1209, 1 230 bp, respectively, which were compared with those available in the GenBank databases. The results showed that the 16S rDNA sequence of 3-28 strain was mostly similar to that of Microbacterium esteraromaticum, NF similar to Cellulosimicrobium cellulans, EW to Chelatococcus asacharovorans and EY to Sphingopyxis terrae, and their sequence similarities were 100%, 97.8%, 98.2% and 99.0%, respectively. The phylogenetic trees of the four strains were derived with DNAMAN and analyzed with Bootstraping. The results demonstrate that the 3-28, NF, EW and EY strains belonged to Microbacterium sp., Cellulosimicrobium sp., Chelatococcus sp. and Sphingopyxis sp., respectively. Fig 3, Tab 1, Ref 22