期刊
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
卷 104, 期 36, 页码 14243-14248出版社
NATL ACAD SCIENCES
DOI: 10.1073/pnas.0607758104
关键词
ligand binding; myoglobin; chemical exchange; infrared spectroscopy
2D-IR exchange spectroscopy has been introduced recently to map chemical exchange networks in equilibrium with subpicosecond time resolution. Here, we demonstrate the generalization of 2D-IR exchange spectroscopy to nonequilibrium systems and its application to map light-triggered migration of ligands between different sites in a protein. Within picoseconds after a photodissociating laser pulse, carbon monoxide ligands relocate from their binding site A at the heme prosthetic group of myoglobin to a primary docking site B in the distal heme pocket. Multiple CO stretching bands are observed for the CO ligand in sites A and B, indicating that several distinct conformational substates of the myoglobin: ligand complex coexist in solution. Exchange cross-peaks between the bands associated with sub-states of heme-bound CO and photodissociated CO in the primary docking site reveal the substate connectivity at physiological temperature.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据