【摘要】 从生长在铀尾矿库区的博落回的根系中,分离出了一株耐铀镉真菌菌株A-2。在固体培养基上,铀和镉对该菌株的最低抑菌浓度(MIC)为160 mg/L和160mg/L,而在液体培养基中,铀和镉对该菌株的MIC为80 mg/L和80 mg/L。经形态学观察和分子鉴定,该菌株属于镰刀菌属,其GenBank登录号为MH978624,可命名为Fusarium sp. A-2。进一步的试验研究结果表明,该菌株在铀镉胁迫下会分泌大量草酸、苹果酸和丁二酸,与铀镉络合,降低了铀镉对菌株的毒性,这可能是该菌株具有高耐铀镉性及能减轻铀镉毒害的机理之一。该菌株在土壤铀镉复合污染治理中具有潜在应用前景。更多还原

【Abstract】 A uranium-cadmium tolerant fungal strain A-2 was isolated from the roots of Macleaya cordata growing in the uranium tailings repository. In solid medium,the minimum inhibitory concentration(MIC) of uranium and cadmium for this strain is 160 mg/L and160 mg/L. In liquid medium,the MIC of uranium and cadmium for this strain is 80 mg/L and 80 mg/L,respectively. The morphological observation and molecular identification confirmed that the strain belongs to the Fusarium,its GenBank accession number is MH978624,and it can be named Fusarium sp. A-2. In addition,the results from further experiments show that under uranium-cadmium co-stress,the strain can secret large amounts of organic acids including oxalic,malic and succinic acids,which can complex with uranium and cadmium to reduce the toxicity of uranium and cadmium to the strain. This may be the mechanism by which the strain can resist high concentrations of uranium and cadmium and reduce uranium and cadmium toxicities. Fusarium sp. A-2 may have potential application prospects in the remediation of the uranium-cadmium contaminated soils.更多还原