Ahmed M S, Ainley K, Parish J H, Hadi S M
Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, India.
Carcinogenesis. 1994 Aug;15(8):1627-30. doi: 10.1093/carcin/15.8.1627.
The flavonoid, quercetin, is known to bind to DNA and, in the presence of Cu(II) and other ions, causes fragmentation of the molecule. We examined whether quercetin might bind to protein and cause similar fragmentation. By using UV spectroscopic and fluorescence quenching experiments we show that quercetin binds to bovine serum albumin and that the complex does, in the presence of Cu(II), lead to fragmentation of the protein. The binding involves binding to tryptophan residues in the albumin. The reaction is not detected in certain other tryptophan-containing proteins. We discuss the possible implications for protein damage by this and other radical-generating reagents.
已知类黄酮槲皮素能与DNA结合，并且在铜离子（II）和其他离子存在的情况下，会导致DNA分子断裂。我们研究了槲皮素是否可能与蛋白质结合并导致类似的断裂。通过紫外光谱和荧光猝灭实验，我们表明槲皮素与牛血清白蛋白结合，并且在铜离子（II）存在的情况下，该复合物确实会导致蛋白质断裂。这种结合涉及与白蛋白中的色氨酸残基结合。在某些其他含色氨酸的蛋白质中未检测到这种反应。我们讨论了这种以及其他产生自由基的试剂对蛋白质损伤的可能影响。
