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The recombinant Saccharomyces cerevisiae expressing human hepatic metallothionein(SC-mt)was constructed for biosorption of uranium(Ⅵ).The gene sequence of mt was modified for codon preference of S.cerevisiae(SC)and synthesized using chemical method.The influences of different experimental parameters such as solution pH,initial concentration,contact time and temperature on adsorption were investigated.The SC and SC-mt showed the highest uranium sorption capacity at initial pH of 6.0 and contact time of 30min and 180min respectively.The adsorption on SC-mt was more favor than SC,in addition the saturated monolayer sorption capacity increased from 238.77 to 285.31 mg/g at 298K.Adsorption kinetics was better described by the pseudo-second-order model and adsorption process could be well defined by the Langmuir isotherm.The thermodynamic parameters of SC-mt,△G°(298K),△H° and △S° were determined to be-23.03,12.29 kJ?mol-1 and 118.51 J?mol-1?K-1,respectively,which demonstrated the sorption process of SC-mt towards uranium was feasible,spontaneous and endothermic in nature.The results indicated that the recombinant SC-mt will be useful in enhancement the effectiveness of uranium biosorption in practice.