摘要： 为了发挥微生物和植物在重金属矿尾区铜污染土壤的共同修复作用,本研究从陕西省凤县矿尾区天蓝苜蓿根瘤中筛选分离到一株抗重金属铜的菌株,定名为CCNWSX0020.该菌株在YMA琼脂平板上抗铜浓度为3.0mmol⁄L,TY液体培养基中抗铜浓度为1.4 mmo1⁄L,因此,它是研究根瘤菌抗铜机制的良好菌株.该菌株经生理生化分析、G+C mo1%测定、DNA同源性分析及16S rDNA序列相似性比较,鉴定为苜蓿中华根瘤菌(Sinorhizobium meliloti),它与苜蓿中华根瘤菌LMG6133的菌株(GenBank登录号为X67222)相似性为99.7%.由于根瘤菌具有独特的生物学地位,即能够与豆科植物形成共生体,这为进一步构建耐重金属的生物体系提供了良好的遗传基础,具有潜在的生态效益和社会效益.

关键词: 重金属, 铜, 根瘤菌, 16S rDNA

Abstract: In recent years, with the development of mining smeltilg and processing of copper industrg soi1 copper pollution is becoming increasingly serious. Thus it is imperative to restore the soil copper contan ination.In this study,in order to develop collaboratiae restoratim activity of microorganisns and plants in the copper-contam inated soils of heavy metals tailing areas an excellent Rhizobiwn strain resistance to copper was screened from mining tailings Fengxian county, Shaanxi province. The strain named CCNW SX0020, resisted to 30 mmo1/L Cu²⁺ on YMA agar plate and to 14 mmol/L Cu²⁺ in TY liquid medium, so it is an important strain using to study the resistant copper mechanisms of microbe.It was prelin inarily identified as a strain of Sinorhizobiun meliloti, based on its physilogical and biochemical characteristics analysis including G+C mol% detemination,DNA homology hybridization and 16S rDNA sequence similarity comparison. The sinilarity betveen CCNW SX0020 and S. meliloti IMG6133(GenBank accession number X67222) was 99.%. Because of Rhizobia with the unique biology status that is being ab1e to form symbiont with legume, which can provide a good genetic base for the further construction of a biology system being tolerant to heavy metals, and as a resu1t, having potential ecological and social benefits.

Key words: Heavymetals, Copper, Rhizobia, 16S rDNA

中图分类号: 

• Q936