Tsotsoros Samantha D, Qu Yun, Farrell Nicholas P
Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284-2006, USA.
Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284-2006, USA.
J Inorg Biochem. 2015 Feb;143:117-22. doi: 10.1016/j.jinorgbio.2014.12.003. Epub 2014 Dec 10.
The interaction of cis-DDP and trans-DDP (DDP=[PtCl2(NH3)2]) with the C-terminal zinc finger (ZF2) of the HIVNCp7 nucleocapsid protein was investigated by fluorescence, circular dichroism, mass spectrometry, and {(1)H, (15)N} HSQC (heteronuclear single quantum coherence) NMR spectroscopy. The rate of reaction differed significantly for the two compounds, with the trans isomer reacting in a significantly faster manner, as expected. {(1)H, (15)N} HSQC NMR of (15)N-labeled compounds with the ZF2 showed the appearance of several new (15)N peaks, consistent with sulfur binding and formation of Pt-S species. Mass spectrometry confirmed the formation of several different Pt-apopeptide/ZF2 adducts. Circular dichroism and fluorescence spectroscopy also indicated conformational changes upon binding while a 33% decrease in fluorescence of the unique tryptophan residue was seen in 72h upon complexation of the cis isomer, while the trans isomer quenched 50% in just 24h.
通过荧光、圆二色性、质谱以及{¹H, ¹⁵N} HSQC(异核单量子相干)核磁共振光谱法,研究了顺铂和反铂(DDP = [PtCl₂(NH₃)₂])与HIV NCp7核衣壳蛋白C端锌指(ZF2)的相互作用。两种化合物的反应速率差异显著,正如预期的那样,反式异构体的反应速度明显更快。¹⁵N标记的化合物与ZF2的{¹H, ¹⁵N} HSQC核磁共振显示出现了几个新的¹⁵N峰,这与硫结合以及Pt-S物种的形成一致。质谱证实形成了几种不同的Pt-脱辅基肽/ZF2加合物。圆二色性和荧光光谱也表明结合后会发生构象变化,顺式异构体络合72小时后,唯一色氨酸残基的荧光降低了33%,而反式异构体在仅24小时内就淬灭了50%。