基于透析法的亚硝基血红蛋白稳定性及机制研究  

Study on Stability and Mechanism of Nitrosohemoglobin Based on Dialysis Method

作　　者：郭婧 袁江兰 康旭 范超 GUO Jing;YUAN Jianglan;KANG Xu;FAN Chao(College of Bioengineering and Food,Hubei University of Technology,Wuhan 430068,China)

机构地区：[1]湖北工业大学生物工程与食品学院,湖北武汉430068

出　　处：《食品工业科技》2022年第17期55-61,共7页Science and Technology of Food Industry

基　　金：湖北省教育厅项目(B2018045);营养米加工关键技术及其蛋白质构变化研究。

摘　　要：本文以猪血红蛋白(Porcine Hemoglobin,PHb)为原料,先利用差示扫描量热法、紫外-可见光谱分析、电位分析等方法对原料PHb的基本特性进行表征,然后制备亚硝基化猪血红蛋白(Porcine nitrosohemoglobin,PHbNO),并利用透析法对PHbNO的结构稳定性及机制进行初步探究。原料分析结果表明PHb的纯度、热稳定性、紫外光谱特征与PHb标品相比无明显差异;紫外-可见光谱分析表明,与PHb相比较,不透析和部分透析的PHbNO中卟啉结构发生明显变化,荧光光谱分析也表明不透析和部分透析的PHbNO结构以及色氨酸或酪氨酸残基周围的微环境发生明显改变,红外及圆二色谱结果显示PHbNO二级结构有明显变化,而彻底透析除去小分子的PHbNO四种光谱特征均与PHb基本相同,因此推断PHb亚硝基化属于可逆化学反应,PHbNO的稳定性取决于溶液中NO的浓度,PHbNO稳定性及机制为:在酸性溶液下,NaNO_(2)生成的NO与PHb中Fe^(2+)发生可逆配位反应生成PHbNO,因此产物稳定性对反应物具有依赖性。本研究为PHbNO的进一步研究和应用提供了理论依据和数据支持。In the work,porcine hemoglobin(PHb) was applied to prepare porcine nitrosohemoglobin(PHbNO),and basic structures and properties of PHb were first characterized by differential scanning calorimetry,UV-Vis spectrum and potential analysis,and then the structural stability and mechanism of PHbNO were studied by dialysis method.The results from analyzing the raw materials PHb indicated that there were no obvious differences in the composition,purity,thermal stability and UV-Vis spectra characteristics by comparing with the standard PHb;the results from UV-Vis showed that porphyrin structure in PHbNO without or in partial dialysis was significantly changed;fluorescence spectroscopic analysis also suggested that structure and microenvironment around tryptophan or tyrosine residues in PHbNO without or in partial dialysis were significantly altered;the results from infrared and circular dichroism indicated that secondary structures of PHbNO changed obviously,however,four spectral characteristics of PHbNO after dialyzing thoroughly to remove small molecules were basically the same as those of PHb.Therefore,it could be inferred that nitrosylation of PHb was reversible,and stability of PHbNO depended on NaNO_(2),and it could be deduced by comprehensive analysis that the stability and mechanism of PHbNO was that NO generated in acidic solution by NaNO_(2)could react with Fe^(2+) in PHb molecule by a reversible style to generate PHbNO,so the stability of PHbNO depended on the reactants.The study could provide a theoretical basis and data for the further study and application of PHbNO.

关 键 词：猪血红蛋白 亚硝基化 透析法 结构特征 稳定性 机制 

分 类 号：TS251.93[轻工技术与工程—农产品加工及贮藏工程]