Manganese resistance and characterization of Enterobacter sp.strain
A bacterial strain exhibiting strong manganese(Mn)tolerance was isolated from paddy soil surround-ing a uranium mine using the enrichment culture method and designated as NM3.The bacterium was identified as belonging to the Enterobacter genus through colony morphology,Gram staining,and 16S rDNA sequence analy-sis.To investigate the adsorption efficiency of Mn2+by the NM3 strain and the associated adsorption mecha-nisms,we employed atomic absorption spectroscopy,scanning electron microscopy,and Fourier-transform in-frared spectroscopy for comprehensive analysis.The results indicated that the strain tolerated Mn2+concentrations of up to 8 000 mg·L-1.After a 60-hour reaction period at a Mn2+concentration of 4 000 mg·L-1,the removal rate reached 93.3％.The primary functional groups involved in this adsorption process were identified as hydroxyl,al-kyl,and amide groups.Further evaluation of the growth-promoting properties of the NM3 strain and its impact on Mn2+accumulation in green vegetables revealed that the strain produced auxin indole-3-acetic acid(IAA),which significantly enhanced the biomass of green vegetables under Mn stress,with increases ranging from 34.13％to 56.09％.Additionally,the Mn2+content in the green vegetables decreased by 50.09％.In summary,the NM3 strain not only demonstrates high tolerance and strong adsorption capacity but also represents a promis-ing new microbial resource for mitigating soil Mn pollution,thereby ensuring vegetable safety.
NETL
NSTL
万方数据
