中文摘要：

细菌紧张 PJ3，从废水孤立并且作为 Arthrobactersp 识别了。细菌基于它的 16S rDNA 基因，能把唑用作唯一的碳，氮和精力来源。紧张 PJ3 的 genomic 图书馆被构造，积极克隆 JM109 (pUCW402 ) 被形成 yellowring 分裂产品的能力为二加氧的表示外面屏蔽。933 bp 的 A 2,3-dihydroxybiphenyl 二加氧(23DHBD ) 基因被 GenSCAN 软件和强风分析在 the3360 bp 发现 pUCW402 的外长的碎片。种系发生的分析证明从紧张 PJ3 的 23DHBD 形成了从在 GenBank 包含大多数已知的 23DHBD 的簇分开的一根深树枝。南部的杂交第一次证实 23DHBDgene 从 Arthrobacter sp 的 genomic 直接存储器存取。PJ3。为了测试基因，工作， recombinant 细菌 BL21 (pETW-8 ) 被构造表示 23DHBD。在 BL21 (pETW-8 ) 的表示水平与 recombinant 细菌 JM109 (pUCW402 ) 和紧张 PJ3 相比是最高的。23DHBD 不是绝对的 Weobserved 特定。活性比与儿茶酚作为底层是更高的 with2,3-dihydroxybiphenyl。底层特性试金建议 23DHBD 在在 Arthrobacter sp 的芳香族化合物简历降级的功课期间为双性人周期的芳香族化合物的劈开是必要的。拉紧 PJ3。

英文摘要：

Bacterium strain PJ3, isolated from wastewater and identified as Arthrobacter sp. bacterium based on its 16S rDNA gene, could use carbazole as the sole carbon, nitrogen and energy source. The genomic library of strain PJ3 was constructed and a positive clone JM109 （pUCW402） was screened out for the expression of dioxygenase by the ability to form yellow ring-fission product. A 2,3-dihydroxybiphenyl dioxygenase （23DHBD） gene of 933 bp was found in the 3360 bp exogenous fragment of pUCW402 by GenSCAN software and BLAST analysis. The phylogenetic analysis showed that 23DHBD from strain PJ3 formed a deep branch separate from a cluster containing most known 23DHBD in GenBank. Southern hybridization confirmed for the first time that the 23DHBD gene was from the genomic DNA of Arthrobacter sp. PJ3. In order to test the gene function, recombinant bacterium BL21 （pETW-8） was constructed to express 23DHBD. The expression level in BL21 （pETW-8） was highest compared with the recombinant bacteria JM109 （pUCW402） and strain PJ3. We observed that 23DHBD was not absolute specific. The enzyme activity was higher with 2,3-dihydroxybiphenyl as a substrate than with catechol. The substrate specificity assay suggested that 23DHBD was essential for cleavage of bi-cyclic aromatic compounds during the course of aromatic compound biodegradation in Arthrobacter sp. strain PJ3.