Biomolecular Formulation and Characterization Sciences, UCB Group, Slough, SL3WE, United Kingdom.
J Am Soc Mass Spectrom. 2020 Jun 3;31(6):1233-1240. doi: 10.1021/jasms.0c00076. Epub 2020 May 22.
A novel histidine-histidine (His-His) photooxidative cross-link has been identified in an IgG4 antibody. It was formed between the side chain of a histidine residue of the antibody and histidine from the formulation buffer. The structure of the cross-link was elucidated using high performance liquid chromatography (HPLC) hyphenated to tandem mass spectrometry (MS/MS) with higher energy collisional dissociation (HCD). The cross-link was found in multiple conformations, as the location of the oxygen varied. Furthermore, the extent of cross-link formation was shown to correlate with the amount of light the antibody was exposed to as well as the solvent accessibility of each modification site.
一种新型的组氨酸-组氨酸（His-His）光氧化交联已在 IgG4 抗体中被鉴定出来。它是在抗体的组氨酸侧链和制剂缓冲液中的组氨酸之间形成的。该交联结构是使用高效液相色谱（HPLC）与串联质谱（MS/MS）结合使用更高能量的碰撞解离（HCD）来阐明的。由于氧的位置不同，该交联以多种构象存在。此外，交联形成的程度与抗体暴露的光量以及每个修饰部位的溶剂可及性相关。
