镉对土壤脲酶动力学特征的影响  

Effect of Cadmium on Kinetic Characteristics of Soil Urease

作　　者：张昀[1] 可欣[2] 关连珠[1] 颜丽[1] 

机构地区：[1]沈阳农业大学土地与环境学院,沈阳110866 [2]沈阳航空航天大学辽宁省清洁能源重点实验室,沈阳110136

出　　处：《沈阳农业大学学报》2010年第3期299-303,共5页Journal of Shenyang Agricultural University

基　　金：辽宁省教育厅创新团队项目(2008T151)

摘　　要：采用室内模拟培养的方法,对镉污染土壤脲酶动力学特征进行了研究。结果表明：脲酶活性随着培养时间的增加而降低,并在第6天达到最大抑制率;同一培养时间内,随着镉浓度的增加,土壤脲酶活性呈现降低的趋势;两种模型拟合结果表明,模型y=c（1＋ax）/（1＋bx）拟合效果较好,说明镉对土壤脲酶活性的抑制为部分抑制;随着镉浓度的增加,Km值不变,Vmax和Vmax/Km呈降低趋势,说明镉对土壤脲酶的作用为非竞争型抑制,即抑制作用为部分非竞争型抑制。The kinetic characteristics of soil urease were studied. The results showed that soil urease was remarkable inhibited with the concentration of Cd adding. While the maximum inhibtion ratio was attained in the sixth incubation day, the relationship between the concentration of Cd^2＋ and soil urease was described by two models, and the model y=c （1＋ax）/（1＋bx） was more suitable. This means that the inhibtion of Cd on soil urease was part of inhibition. The Ko, was not effected, but the Vmax and Vmax/Km were lowed while Cd adding. This results showed that the enzymatic reaction mechanism was noneompetion-inhibitory between soil urease and cadmium.

关 键 词：镉 脲酶 酶动力学 土壤污染 

分 类 号：S154.2[农业科学—土壤学]