Arthrobacter sp. W1苯酚降解特性及其羟化酶基因获取

Characteristics of Arthrobacter sp. W1 for phenol biodegradation and acquisition of phenol hydroxylase gene

摘要:

为获得适应高盐环境的苯酚降解菌及其相关降解基因,从活性污泥中筛选得到一株耐盐苯酚降解菌W1.利用16S rRNA基因序列鉴定该菌株,并考察了其降解特性;同时,采用Tail-PCR方法对菌株苯酚羟化酶基因进行侧翼调取.结果表明:菌株W1为节杆菌(Arthrobacter sp.),能在质量分数为1%～10%的NaCl溶液中以苯酚为唯一碳源及能源生长,并能降解对甲基酚、水杨酸、对苯二酚等多种芳香化合物.在质量分数为5%的NaCl溶液中,菌株W1对质量浓度为1 000 mg.L-1的苯酚降解率高达90%以上.侧翼获取的基因全长约为6 kb,其中,编码苯酚羟化酶大亚基基因的全长序列与Alcaligenes sp.相应序列具有较高的同源性,约为93%.

Abstract:

To obtain novel salt-tolerant phenol-degrading bacteria and amplify the corresponding genes,a bacterium named W1 was isolated from the active sludge samples.16S rRNA sequence analysis was used to identify the bacterium,and characteristics for phenol biodegradation were also studied.The 5’-and 3’-flanking regions of gene encoding the phenol hydroxylase were amplified from strain W1 by TAIL-PCR method.1wt%-10wt% was showed that strain W1 was identified as Arthrobacter sp.The strain was capable of growing in the medium with 1wt%-10wt% NaCl and utilizing phenol as the sole carbon and energy source.And it could also degrade some other aromatic compounds such as p-methylphenol,salicylic acid and p-hydroquinone,etc.When concentration of NaCl was about 5wt%,1 000 mg·L-1 phenol could be degraded more than 90% by strain W1.The complete gene cluster was about 6 kb,of which the gene encoding the large subunit of phenol hydroxylase exhibited the highest similarity about 93% with the corresponding gene of Alcaligenes sp.