中文摘要：

通过PCR的方法从六六六降解菌Sphingomonassp．BHC-A扩增出完整的脱氯化氢酶基因l／hA。将其克隆到含有mini-Tn5的自杀性质粒pUT4K上，构建成质粒pUT／mini-Tn5-linA．通过三亲杂交，在辅助质粒RK600的帮助下，将pUT／mini-Tn5-linA转移到一株高效降解多菌灵菌株Rhodococcussp．DJL-6中。利用mini-Tn5的转座作用将linA基因整合到DJL-6的染色体DNA上，得到工程菌株DJL-6A。该工程菌具有同时降解多菌灵和六六六的功能，且对于初始浓度为0．05μg／mL和5μg／mL的六六六的降解活性与亲本菌株BHC-A相当。在不加任何选择压力的条件下工程菌株进行连续传代，结果证明linA基因可以持续稳定的存在于宿主的染色体DNA上。

英文摘要：

The complete dehydrochlorinase gene linA of a γ-hexachlorocyclohexane （γ-HCH） degrading strain Sphingomonas sp. BHC-A, containing promoter and Shine-Dalgarno sequence （SD sequence）, was amplified by PCR. The linA gene was inserted into NotI-cut transposon vector pUT/mini-Tn5 （Km^t） to get a novel transposon vector pUTImini-Tn5-1inA. With the helper plasmid RK600, the transposon vector pUT/mini-Tn5-1inA was introduced into one carbendazim degrading gram-positive strain Rhodococcus sp. DJL-6 by triparental conjugation and then the dehydrochlorinase gene linA was integrated into the chromosome of Rhodococcus sp. DJL-6 by the transposon mini-Tn5. The selected multifunctional genetically engineered strain DJL-6A could degrade γ-HCH and carbendazim simultaneously. The dehydrochlorinase activity of DJL-6A was as strong as that of Sphingomonas sp. BHC-A in 0.05 and 5 μg/mL initial γ-HCH concentration. The linA of the strain DJL-6A was genetically stabile after successive plating DJL-6A for 30 days on nonselective media.