耐镉马克思克鲁维酵母重金属镉吸附特性的研究  

The characteristics of cadmium adsorption by Cd-resisting Kluyveromyces marxianus YS-K1

作　　者：王小波[1] 李学如[1] 茆灿泉[1] 江南屏[1] 郭泰林[1] 

机构地区：[1]西南交通大学生命科学与工程学院,四川成都610031

出　　处：《菌物学报》2013年第5期868-875,共8页Mycosystema

基　　金：国家高技术研究发展计划(863计划)(No.2006AA06Z353);中央高校基本科研业务费专项资金(No.SWJTU11ZT25)

摘　　要：菌株YS-K1是从镉污染土壤中筛选获得的一株耐镉马克思克鲁维酵母Kluyveromyces marxianus YS-K1,对其镉吸附特性研究结果表明,该菌对镉具有良好的耐受性和吸附性,即使在镉浓度高达140mg/L的培养基中也能生长,当镉浓度在30mg/L以下时,24h后能吸附溶液中90%以上的镉,且最佳吸附条件为pH6.0,温度30℃。该菌所吸附的镉大部分集中在细胞壁上,占总吸附镉的76%,细胞膜上的占9%,细胞质中的占15%;能量抑制剂2,4-二硝基苯酚(DNP)和二环己基碳二亚胺(DCC),分别能降低菌株15%和22%的镉吸附量。在Kluyveromyces marxianus YS-K1细胞中,锌离子与镉离子有共用的结合位点,锌离子不仅会与镉离子竞争细胞表面的结合位点,减少其对镉的吸附量,而且也会与镉离子竞争进入细胞的通道位点,减少其对镉的积累量,同时能部分恢复镉离子对菌株生长的抑制作用。The characteristics of cadmium adsorption by Kluyveromyces marxianus YS-K1, a Cd-resisting yeast isolated from polluted soil, were studied. The results showed that Kluyveromyces marxianus YS-K1 had high resistance and effectual adsorption to cadmium. Even under cadmium concentration of 140mg/L it could grow up well. Under concentration below 30mg/L, the strain could also adsorb more than 90% of the cadmium in 24 hour incubation under the optimal pH value of 6.0 and the optimal temperature of 30℃. 76% of adsorbed cadmium was concentrated on cell wall, 9% on membrane and l 5% in cytoplasm. The cadmium adsorption reduced 15% and 22% under the treatment of metabolic inhibitors DNP and DCC. Zinc not only competed with cadmium for cell surface binding sites, and reduced biosorption ability ofKluyveromyces marxianus YS-K1 to cadmium, but also competed in occupying the binding sites of entrance passageway of the cells, reducing bioaccumulation of cadmium, and recovering the inhibition activity of cadmium to the strain.

关 键 词：马克思克鲁维酵母YS—K1 镉 能量抑制剂 锌 吸附 积累 

分 类 号：X172[环境科学与工程—环境科学]