甲烷氧化菌素(Methanobactin,Mb)是由甲烷氧化细菌分泌到细胞外的小分子荧光肽,同时也具有金属鳌合的生物特性可将自然界中的Hg(Ⅱ)还原成Hg(0)吸附于细胞表面且不挥发.甲烷氧化菌具有在高汞离子浓度环境下的耐受性,具有清除环境中汞的能力.Mb能完成多种生理功能,包括汞的吸附以及汞的解毒.本文以甲基弯菌(Methylosinus trichosporium)IMV3011发酵液为原料,使用大孔树脂HP-20对其进行分离纯化获得Mb,分析Mb在细胞外与汞的特异性结合以及是否受到铜离子干扰,确定Mb纯化后与汞的结合的反应时间为5min,结合摩尔比为2∶1,汞的吸附率达70％.最佳发酵碳源为甲烷,最佳发酵周期为5d.通过细胞生长曲线确定细胞耐受汞离子浓度为15umol· L-1,汞离子的存在使细胞生长的延滞期变长,对数生长期减小,最大比生长速率降低.%Methanobactin (Mb) is a small molecule fluorescent peptide secreted by methane oxidizing bacteria into the cell,and also has the biological properties of metal chelation to restore Hg (Ⅱ) in nature to Hg (0) Cell surface and not volatile.Methane oxidizing bacteria has the ability to tolerate mercury in the environment with high mercury ion concentration.Mb can perform a variety of physiological functions,including mercury adsorption and mercury detoxification.In this paper,methyl bromide (Methylosinus trichosporium) IMV3011 fermentation broth was used as raw material and purified by macroporous resin HP-20 to obtain Mb.The specific binding of Mb to extracellular and mercury was analyzed and whether copper ions were interfered with The reaction time of Mb purification with mercury was 5 min,the molar ratio was 2∶1,and the adsorption rate of mercury was 70％.The best fermentation carbon source is methane,the best fermentation cycle is 5 days.The cell growth curve was used to determine the concentration of mercury ion at 15umol ·L-1.The presence of mercury ions prolonged the growth of cell growth,decreased the logarithmic growth phase and decreased the maximum specific growth rate.
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