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本文通过电喷雾质谱对流基乙醇还原二硫键的过程进行了动态监测。通过对还原过程中质量数变化的监测，确定了重组人肿瘤坏死因子中二硫键的数目，正确区分正常表达的重组人肿瘤坏死因子和基因工程改构产品，为基因工程产品鉴定提供了一条新的途径。蛋白质中的二硫键在蛋白质高级结构的稳定性及生物学活性中都有着重要的作用［1］，研究二硫键的结合情况始终是生化领域的一个重要课题。二硫键是两个半胱氨酸残基之间形成的一个化学健，它使多肽键的不同区域紧密连接，维持分子折叠结构的稳定性。分子中是否存在二硫键，以及二硫键是否正确结合在蛋白质化学中是一个十分重要的问题。人肿瘤坏死因子（hTNF）是近年来研究较广泛的一种细胞因子，其一级结构中第69位和101位为半胱氨酸，在分子内形威一对二硫键［2］。在hTNF的蛋白质工程研究中，有人将69位和101位Cys的分别用AsP和Arg取代，获得改构的TNF仍具有TNF的生物学活性。因此鉴定rhTNF中是否存在二硫键成为区分rhTNF和改构TNF的重要途径。
In this paper, electrospray ionization mass spectrometry was used to dynamically monitor the process of reduction of disulfide bonds by hydroethyl alcohol. Through the monitoring of the change of mass number during the reduction, the number of disulfide bonds in recombinant human tumor necrosis factor was determined, and the correctly expressed recombinant human tumor necrosis factor and genetically engineered products were correctly distinguished, thus providing a gene engineering product identification New way. Disulfide bonds in proteins play an important role in the stability and biological activity of high-order structures of proteins [1]. It is always an important topic in the field of biochemistry to study the disulfide bond. Disulfide bonds are a chemical bond formed between two cysteine residues that tightly link different regions of the polypeptide bond and maintain the stability of the folded structure of the molecule. The existence of disulfide bonds in molecules, and the correct disulfide bond in protein chemistry is a very important issue. Human tumor necrosis factor (hTNF) is a more widely studied cytokine in recent years. Its primary structure is the cysteine at the 69th and the 101st positions, forming a pair of disulfide bonds in the molecule [2]. In the protein engineering study of hTNF, it was substituted by AsP and Arg at the 69th and the 101st Cys, respectively, so that the modified TNF still possessed the biological activity of TNF. Identification of disulfide bonds in rhTNF is therefore an important way to distinguish between rhTNF and TNF.