• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of mass spectrometry: JMS >Formation of metal complex ions from amino acid in the presence of Li ~+, Na~+ and K~+ by electrospray ionization: Metal replacement of hydrogen in the ligands
【24h】

Formation of metal complex ions from amino acid in the presence of Li ~+, Na~+ and K~+ by electrospray ionization: Metal replacement of hydrogen in the ligands

机译：Li〜+，Na〜+和K〜+存在下通过电喷雾电离从氨基酸形成金属络离子：配体中氢的金属置换

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Alkali metal cations easily form complexes with proteins in biological systems; understanding amino acid clusters with these cations can provide useful insight into their behaviors at the molecular level including diagnosis and therapy of related diseases. For the purpose of characterization of basic interaction between amino acids and alkali metal, each of the 20 naturally occurring amino acids were ionized in the presence of lithium, sodium and potassium cations by electrospray ionization, and the resulting product ions were analyzed. We focus our attention on the gas phase alkali metal ion-proton exchanged complexes in current study, specifically complexes with serine, threonine, asparagine and glutamine, which share characteristic pattern unlike other amino acids. All amino acids generated [M ~+ H]~+ and [M ~+ Na]~+ ions, where M stands for the neutral amino acid. Serine, threonine, asparagine and glutamine generated cluster ions of [nM - nH ~+ (n ~+ 1)Na]~+ and [nM - (n - 1)H ~+ (n - 1)Na ~+ K]~+, where n = 1-7. While the (M - H ~+ Li) and (M - H ~+ K) species were not observed, the neutral (M - H ~+ Na) species formed by proton-sodium cation exchange had a highly stable cyclic structure with ketone and amine ligand sites, suggesting that (M - H + Na) serves as a building block in cluster ion formation. Cluster ion intensity distributions of [nM - nH + (n ~+ 1)Na]~+ and [nM - (n - 1)H ~+ (n - 1)Na ~+ K]~+ showed a magic number at n = 3 and 4, respectively. Extensive B3LYP-DFT quantum mechanical calculations were carried out to elucidate the geometry and energy of the cluster ions, and they provided a reasonable explanation for the stability and structure of the cluster ions.
机译：碱金属阳离子很容易在生物系统中与蛋白质形成络合物。了解带有这些阳离子的氨基酸簇可以在分子水平上为他们的行为提供有用的见解，包括相关疾病的诊断和治疗。为了表征氨基酸和碱金属之间的基本相互作用，在锂，钠和钾阳离子存在下，通过电喷雾电离将20种天然氨基酸中的每一种离子化，并分析所得的产物离子。在当前的研究中，我们将注意力集中在气相碱金属离子-质子交换配合物上，特别是与丝氨酸，苏氨酸，天冬酰胺和谷氨酰胺配合物，它们具有与其他氨基酸不同的特征模式。所有氨基酸均产生[M〜+ H]〜+和[M〜+ Na]〜+离子，其中M代表中性氨基酸。丝氨酸，苏氨酸，天冬酰胺和谷氨酰胺生成[nM-nH〜+（n〜+ 1）Na]〜+和[nM-（n-1）H〜+（n-1）Na〜+ K]〜的簇离子+，其中n = 1-7。虽然未观察到（M-H〜+ Li）和（M-H〜+ K）物种，但通过质子钠阳离子交换形成的中性（M-H〜+ Na）物种具有高度稳定的与酮的环状结构和胺配体位点，表明（MH + Na）是簇离子形成的基础。 [nM-nH +（n〜+ 1）Na]〜+和[nM-（n-1）H〜+（n-1）Na〜+ K]〜+的簇离子强度分布在n处显示幻数= 3和4。进行了广泛的B3LYP-DFT量子力学计算，阐明了簇离子的几何形状和能量，为簇离子的稳定性和结构提供了合理的解释。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号