羊毛角蛋白中巯基含量的测定及其应用  

Determination of Sulfhydryl Content in Wool Keratin and Its Application

作　　者：陈光 袁久刚[1] 向宇 范雪荣[1] 王平[1] 王强[1] CHEN Guang;YUAN Jiugang;XIANG Yu;FAN Xuerong;WANG Ping;WANG Qiang(Key Laboratory of Eco-textiles,Ministry of Education,Jiangnan University,Wuxi 214122,China)

机构地区：[1]江南大学生态纺织教育部重点实验室,无锡214122

出　　处：《材料导报》2021年第14期14176-14179,共4页Materials Reports

基　　金：国家自然科学基金(31771039);国家重点研究发展计划(2017YFB0309200);中央高校基本科研业务费专项资金项目(JUSRP51717A)。

摘　　要：羊毛角蛋白中含有大量半胱氨酸残基,这些半胱氨酸残基中巯基之间的相互作用对维持蛋白质的二级和三级结构有着重要的意义。为了测定羊毛角蛋白中的巯基含量,本工作在不同变性剂以及pH值体系中详细比较了4,4’-二吡啶基二硫(DPS)法与经典的埃尔曼试剂法测定巯基时的响应性。结果发现:在pH值为7.0、8 mol/L尿素、1%十二烷基硫酸钠(SDS)、3 mmol/L乙二胺四乙酸(EDTA)的缓冲液体系中,DPS法相较于埃尔曼试剂法具有更高的巯基响应性。因此,在上述缓冲液体系中,采用DPS法验证了过氧化氢溶液对羊毛角蛋白中巯基的氧化作用以及高温对羊毛纤维蛋白中二硫键的破坏作用。实验结论表明,DPS法准确可靠,适用于羊毛角蛋白中巯基含量的测定。Wool keratin contains a large number of cysteine residues.The interaction between the sulfhydryl groups in these cysteine residues is important for maintaining the secondary and tertiary structure of the protein.In order to determine the sulfhydryl group content in wool keratin,the responsiveness of the sulfhydryl group by the 4,4’-dipyridyldisulfide(DPS)method and the classic Ellman’s reagent method was compared in detail in different denaturants and pH systems.The study found that the DPS method had higher sulfhydryl responsiveness than the Ellman’s reagent method at pH 7.0,8 mol/L urea,1% sodium dodecyl sulfate(SDS)and 3 mmol/L ethylenediamine tetraacetic acid(EDTA)buffer system.Therefore,the oxidation of sulfhydryl groups in wool keratin by hydrogen peroxide solution and the destruction of disulfide bonds in wool fiber protein by high temperature were verified by the DPS method in the above buffer system.The experimental results showed that the DPS method could be accurately and reliably applied to the determination of sulfhydryl content in wool keratin.

关 键 词：羊毛角蛋白 巯基 4 4’-二吡啶基二硫(DPS)法 埃尔曼试剂法 

分 类 号：O629.73[理学—有机化学]