Department of Chemistry, University of Florence , Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
Inorg Chem. 2013 Dec 16;52(24):13827-9. doi: 10.1021/ic402611m. Epub 2013 Nov 20.
The reactivity of cis-diamminediiodidoplatinum(II), cis-PtI2(NH3)2, the iodo analogue of cisplatin, with hen egg white lysozyme (HEWL) was investigated by electrospray ionization mass spectrometry and X-ray crystallography. Interestingly, the study compound forms a stable 1:1 protein adduct for which the crystal structure was solved at 1.99 Å resolution. In this adduct, the Pt(II) center, upon release of one ammonia ligand, selectively coordinates to the imidazole of His15. Both iodide ligands remain bound to platinum, with this being a highly peculiar and unexpected feature. Notably, two equivalent modes of Pt(II) binding are possible that differ only in the location of I atoms with respect to ND1 of His15. The structure of the adduct was compared with that of HEWL-cisplatin, previously described; differences are stressed and their important mechanistic implications discussed.
采用电喷雾质谱法和 X 射线晶体学研究了顺式-二氨二碘化铂（II）（顺式-PtI2（NH3）2，顺铂的碘类似物）与鸡卵清溶菌酶（HEWL）的反应性。有趣的是，研究化合物形成了稳定的 1:1 蛋白质加合物，其晶体结构在 1.99Å 分辨率下得到解决。在该加合物中，Pt（II）中心在释放一个氨配体后，选择性地与 His15 的咪唑配位。两个碘配体都与铂结合，这是一个非常特殊和出乎意料的特征。值得注意的是，可能存在两种等效的 Pt（II）结合模式，仅在相对于 His15 的 ND1 的 I 原子的位置上有所不同。加合物的结构与先前描述的 HEWL-顺铂的结构进行了比较；强调了差异，并讨论了它们的重要机制意义。
