The Nature of Phosphorylated Chrysin−Protein Interactions Involved in Noncovalent Complex Formation by Electrospray Ionization Mass Spectroscopy

In the work described in this paper, chrysin was phosphorylated by a modified Atheron−Todd reaction. The
structure of phosphorylated chrysin was determined by
elemental analysis, NMR, ESI-MS/MS, and X-ray data.
Electrospray ionization results showed that the phosphorylated flavonoids could form noncovalent complexes with
many proteins, such as lysozyme, myoglobin, bovine
insulin, and cytochrome c, while noncovalent complexes
were not detected in the mixed solution of the chrysin and
proteins. The research shows that the phosphorylated
flavonoids possess relatively stronger affinities and form
noncovalent complexes with the proteins more easily than
the non-phosphorylated compounds.

本文所涉研究中，研究人员借助改良的Atheron-Todd反应（modified Atheron−Todd reaction）对白杨素（chrysin）进行了磷酸化修饰。通过元素分析（elemental analysis）、核磁共振波谱（Nuclear Magnetic Resonance, NMR）、电喷雾串联质谱（Electrospray ionization tandem mass spectrometry, ESI-MS/MS）及X射线衍射数据（X-ray data）对磷酸化白杨素的结构进行了确证。电喷雾电离测试结果显示，磷酸化黄酮类化合物（flavonoids）可与多种蛋白质形成非共价复合物（noncovalent complexes），涉及的蛋白质包括溶菌酶（lysozyme）、肌红蛋白（myoglobin）、牛胰岛素（bovine insulin）及细胞色素c（cytochrome c）；而在未磷酸化的白杨素与蛋白质的混合溶液中，并未检测到非共价复合物的存在。本研究证实，相较于未经过磷酸化修饰的母体化合物（non-phosphorylated compounds），磷酸化黄酮类化合物与蛋白质的结合亲和力更强，且更易与蛋白质形成非共价复合物。