玉门油田污染荒漠土壤石油降解菌多样性  

Diversity of Oil-Degrading Bacteria Isolated from Oil-Contaminated Desert Soil of Yumen Oilfield

作　　者：杨智[1] 陈吉祥[2] 周永涛 张彦 李彦林[1] 王永刚[1] 周敏[2] 

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050 [2]兰州理工大学石油化工学院,甘肃兰州730050 [3]中石油北京天然气管道有限公司,北京100101

出　　处：《环境科学研究》2017年第5期799-808,共10页Research of Environmental Sciences

基　　金：国家自然科学基金项目(31272694);中国石油天然气股份有限公司天然气与管道分公司科研项目(2014D-4610-0501)

摘　　要：为探索石油污染荒漠土壤石油降解微生物多样性、筛选高效石油降解菌,采用涂布平板法从石油污染荒漠土壤分离具有石油降解能力细菌,采用细菌形态观察和16S rRNA基因序列分析其多样性,并设计特异性引物,对分离细菌降解相关基因进行检测.结果表明,分离的37株细菌分别属于放线菌纲(Actinobacteria)、γ变形菌纲(Gammaproteobacteria)、β变形菌纲(Betaproteobacteria)、芽孢杆菌纲(Bacilli)和α变形菌纲(Alphaproteobacteria),分别占35.14%、32.43%、13.51%、13.51%、5.41%,归属于21个属的34个种类.优势菌属为假单胞菌属(Pseudomonas)、红球菌属(Rhodococcus)、微球菌属(Micrococcus)、寡养单胞菌属(Stenotrophomonas)、无色杆菌属(Achromobacter)和葡萄球菌属(Staphylococcus),占总数的51.35%,其中有36株细菌能以石油为唯一碳源稳定生长,对原油有明显的降解能力.在石油质量浓度为1 500 mg/L的基础培养基中,菌株YM43在培养7d后对石油的降解率达55.47%,另有8株细菌的降解率不低于30.55%,11株细菌的降解率介于10.05%~28.37%,18株细菌的降解率不高于8.05%.PCR检测表明,有25株细菌含有烷烃单加氧酶基因,6株含芳烃双加氧酶基因,6株含联苯双加氧酶基因,4株含萘双加氧酶基因,3株含甲苯双加氧酶基因,2株含邻苯二酚双加氧酶基因.研究显示,石油污染荒漠土壤中可培养细菌具有高度多样性,分离的菌株有较强的石油降解能力,其降解功能与所存在的降解基因有关.Microbial resources are rich in soil environments. The most potential bacteria for oil degradation were isolated from areas contaminated by oil. Biodegradation by microorganisms is more favorable than chemical treatment for dealing with oil pollution. In order to explore the diversity of the degrading microorganisms of oil-contaminated desert soil and screen the efficient oil-degrading bacteria, the spread plate method was used to isolate the oil-degrading bacteria. Bacterial morphology and 16S rRNA gene sequence analysis were used to identify the isolates. The results indicated that the 37 isolated bacterial strains belonged to 21 genera and 34 species belonging to Actinobacteria （35.14%）, Gammaproteobacteria （32.43%）, Betaproteobacteria （13.51%）, Bacilli （13.51%） and Alphaproteobacteria （5.41%）. The six predominant bacterial genera were found to be Pseudomonas, Rhodococcus, Micrococcus, Stenotrophomonas, Achromobacte and Staphylococcus, which accounted for 51.35% of the total isolated strains. Further experiments revealed that 36 strains demonstrated good adaptability to crude oil and grew well in medium using crude oil as the sole carbon and energy source. After being cultured for seven days in medium with an oil concentration of 1500 mg/L, the oil-degrading rates of eight strains were not less than 30.55%. The rates of 11 strains were measured to be between 10.05% and 28.37%, whereas the rates of 18 strains were not more than 8.05%. The highest rate was obtained by stain YM43. The PCR detection results showed that 25 strains of the isolated bacteria contained alkane monooxygenase genes, six strains had aromatic dioxygenase genes, six strains existed biphenyl dioxygenase genes, four strains contained naphthalene dioxygenase genes, while three strains contained toluene dioxygenase genes. Catechol dioxygenase genes were detected in two strains. The conclusions illustrate that a high diversity of culturable oil-degrading bacteria existed in the oil-contaminated desert soil, and the separated s

关 键 词：荒漠土壤 石油降解菌 16S RRNA 多样性 降解基因 

分 类 号：X172[环境科学与工程—环境科学]