青藏高原土壤中一株低温原油降解菌的分离鉴定及其原油降解特性

Isolation,identification and degradation characteristics of a low temperature crude oil degrading bacteria strain from the soil of Tibetan Plateau

从青藏高原班戈桥地区土壤中分离到一株能利用原油为碳源生长的细菌(BGQ-6).通过16S rRNA基因序列比对及Biolog GENⅢ鉴定板确定该菌株为Rhodococcus qingshengii.将生长至对数期的菌株接入MM培养基,10℃、150 rpm条件下培养15 d后,通过GC法检测到该菌对原油的总降解率为74.14%,且对直链烷烃、支链烷烃、环烷烃和芳香烃等60种烃类有较高的降解率.通过特异性基因扩增检测到该菌株基因组中具有4个alk B和1个alm A两种烷烃羟化酶基因.

A bacteria strain（ BGQ-6） was isolated from the soil sample in the Bangeqiao area of the Tibetan Plateau. The BGQ-6 can grow well within the medium with crude oil as carbon source. The 16 S rRNA gene sequence and Biolog GEN III analysis show ed that this strain has a high similarity with Rhodococcus qingshengii,and it is identified as Rhodococcus qingshengii BGQ-6. The strain at the logarithmic grow th phase was incubated to the MMmedium and cultured at 10 ℃ and 150 rpm for 15 d,and the results of gas chromatograph（ GC）detection show ed that BGQ-6 strain can degraded by 74. 14% of crude oil added in the medium. Further analysis indicates that BGQ-6 is able to degrade 60 kinds of hydrocarbon with a high degradation rate,including alkanes,alkane,cyclones,and aromatic hydrocarbon. Using the method of degenerate PCR,we identified tw o kinds of oil degrading genes,alk B and alm A,which encode hydroxylases,and alkB has 4 members and almA has 1 copy in the genome of BGQ-6.