STRUCTURAL STUDIES OF RHODIUM(II)-ACETATE COMPLEXES WITH CYSTEINE AND ITS DERIVA

乙酸铑(II)-半胱氨酸及其衍生物配合物的结构研究

• 批准号: 8362268
• 负责人: FARIDEH JALILEHVAND
• 金额: $ 0.03万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8362268
• 关键词: Acetates; Amino Acids; Binding; Carbon Dioxide; Cisplatin; Complex; Cysteine; DNA; DNA biosynthesis; DNA-Directed DNA Polymerase; Enzymes; Funding; Grant; Ions; Lead; Ligands; Metals; Methods; National Center for Research Resources; Nucleotides; Penicillamine; Principal Investigator; Proteins; Radiation; Reaction; Relative (related person); Replication-Associated Process; Research; Research Infrastructure; Resources; Rhodium; Source; Structure; Sulfhydryl Compounds; Toxic effect; United States National Institutes of Health; base; carboxylate; cost; mecysteine; prevent; solid state; structural biology

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The antitumor activity of rhodium(II) carboxylates, [Rh2(RCOO)4], was discovered in 1976; however, its rather high toxicity relative to cisplatin, Pt(NH3)2Cl2, has prevented it from becoming clinically approved. This class of dirhodium(II) compounds can interact with both DNA and proteins: they can form complexes with the DNA nucleotide bases, interrupting the DNA replication process, or bind to the amino acid residues of proteins. Earlier studies suggest that reaction of rhodium(II) carboxylates with free thiol (-SH) containing groups, such as aminoacid cysteine, results in decomposition of the dirhodium complex, breaking the Rh-Rh bond and releasing CO2. It has been proposed that such a reaction with free thiol group(s) at or near the active center of an enzyme, such as DNA polymerase, can lead to inactivation of the enzyme; this view is in parallel with the toxicity effects of the rhodium(II) carboxylates. Pnematikakis et al. investigated complexes formed between rhodium(II) acetate, [Rh2(CH3COO)4], with L-cysteine, cysteine methyl-ester and D- penicillamine (3,3'-dimethyl cysteine) in the solid state, using IR and EPR spectroscopic methods, and concluded that these ligands form (N,S)- bound monomeric Rh(II) complexes. However, no details about the local structure around Rh(II) ions in these complexes, i.e. metal-ligand bond distances, is available.

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 Rh(II)羧酸盐[Rh2(RCOO)4]的抗肿瘤活性于1976年被发现，然而，相对于顺铂，其相当高的毒性，使其无法获得临床批准。这类化合物可以与DNA和蛋白质相互作用：它们可以与DNA核苷酸碱基形成络合物，中断DNA复制过程，或与蛋白质的氨基酸残基结合。早期的研究表明，Rh(II)羧酸盐与含有游离硫醇(-SH)的基团(如氨基酸半胱氨酸)反应，导致Dirhodium络合物分解，打破Rh-Rh键并释放二氧化碳。有人提出，在酶的活性中心或附近与游离的硫醇基团(S)反应可导致酶的失活；这一观点与Rh(II)羧酸盐的毒性效应是平行的。Pnematikakis等人。用红外光谱和电子顺磁共振方法研究了醋酸Rh(II)[Rh_2(CH_3COO)_4]与L-半胱氨酸、半胱氨酸甲酯和D-青霉胺(3，3‘-二甲基半胱氨酸)形成的固体络合物，认为这些配体形成了(N，S)键合的单体Rh(II)络合物。然而，关于这些络合物中Rh(II)离子周围的局部结构，即金属-配体键长，还没有详细的信息。