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目的 探讨土壤中萘降解菌对萘和重金属双重污染的耐受性.方法 对油田石油污染土壤中分离到的一株高效萘降解菌——伯克霍尔德菌(Burkholderia sp.)TN的重金属耐受性、铅富集机制及在土壤生物修复中的应用进行研究,以分光光度法测定不同Pb2+浓度(100～500 mg/L)对菌悬液吸光度的影响,以电感耦合等离子体发射光谱仪(ICP-OES)测定培养基中重金属(50 mg/L,Pb2+,Zn2+,Cu2+和Cd3+)在菌体培养液、细胞壁、细胞内富集物中的分布,以扫描电镜(SEM)、能谱仪(EDS)和傅里叶变换红外光谱(FTIR)观察100 mg/L Pb2+对菌体形态、元素及官能团分布的影响.结果 菌株TN对Pb2+的最高耐受浓度为500 mg/L并可耐受一定浓度的Zn2+、Cu2+和Cd3+,TN对pb2+富集程度最高,细胞壁及胞内富集率达到98.33％;菌体蓄积pb2+后细胞壁表面有沉淀物附着并有铅元素检出,对pb2+的蓄积主要依靠细胞壁上的羧基、羟基、酰胺基及磷酸基团;将TN菌株接种到含有2.5 mg/g萘及200 mg/L Pb2+的灭菌土壤中,经过13d室温培养之后,萘的去除率为94.29％.结论 TN菌株对Pb2+、Zn2+、Cu2+和Cd3均具有一定的耐受性,对pb2+的富集能力强.该菌株能够依靠细胞壁上的活性基团富集pb2+,适用于萘和pb2+双重胁迫的土壤修复.“,”Objective To explore the lead tolerance of a naphthalene-degrading strain TN isolated from oil contaminated soil of oil field.Methods A naphthalene-degrading strain TN isolated from oil contaminated soil of oil field was collected for research on the resistance to different heavy metals,the mechanism of lead accumulation and application in soil bioremediation.The mechanism of lead accumulation by stain TN was evaluated by inductively coupled plasma-optical emission spectrometry (ICP-OES),scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and infrared spectroscopy (FTIR).Results The results of resistance experiments showed that the maximum tolerated concentration of lead was 500 mg/L and could tolerate a certain concentration of Zn2+,Cu2+ and Cd3+.The adsorption rate of Pb2+ was the highest (98.33％) by cell wall and intracellular.The granular lead was precipitated on the cell wall of bacteria based on the possible functional groups such as carboxyl,hydroxyl,amide group and phosphoric acid group.After inoculating strain TN into the autoclaved soils containing 0.25％ naphthalene and 200 mg/L Pb2+,incubating it at room temperature for 13 days,94.29％ naphthalene was removed.Conclusion TN strain has a certain resistance to heavy metals such as Pb2+,Zn2+,Cu2+ and Cd3+.This strain can enrich Pb2+ by the active groups on the cell wall and better effect of degradation was realized by applying to the remediation of naphthalene and Pb2+ contaminated soil.