title: The reaction of dichlorodiammineplatinum(II), [PtCl2(NH3)2], isomers with zinc fingers.
abstract: 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.
authors.affiliation: Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284-2006, USA.
authors.forename: Samantha D
authors.initials: SD
authors.lastname: Tsotsoros
authors.affiliation: Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284-2006, USA.
authors.forename: Yun
authors.initials: Y
authors.lastname: Qu
authors.affiliation: Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284-2006, USA. Electronic address: npfarrell@vcu.edu.
authors.forename: Nicholas P
authors.initials: NP
authors.lastname: Farrell
mesh_terms: D002942:Circular Dichroism; D002945:Cisplatin / Q000737:chemistry*; D015497:HIV-1; D013058:Mass Spectrometry; D019906:Nuclear Magnetic Resonance, Biomolecular; D011485:Protein Binding; D013237:Stereoisomerism; D016335:Zinc Fingers; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000737:chemistry*
chemical_list: C071884:NCP7 protein, Human immunodeficiency virus 1; D054301:gag Gene Products, Human Immunodeficiency Virus; D002945:Cisplatin
keywords: Cisplatin; HIVNCp7; Transplatin; Zinc finger