FTIR investigation of the conformational properties of the cyanide bound human hemoglobin
FTIR investigation of the conformational properties of the cyanide bound human hemoglobin
复制标题
DOI：
10.1016/s0924-2031(02)00008-5
复制
发表时间：
2002-11-04
影响因子：
2.5
通讯作者：
Al-Mustafa, JI
中科院分区：
文献类型：
--
作者：
Al-Mustafa, JI
本文研究了氰化高铁血红蛋白（Hb-CN）在C-N伸缩区的4cm（-1）分辨红外光谱。血红蛋白连接的各种同位素形式的氰离子的FTIR光谱支持存在三种构象状态的Hb-CN。在pH值为7.5的磷酸钾缓冲液中，天然丰度Hb-CN在2116、2122和2127 cm（-1）处观察到三条带。对于Hb-（CN）-C-12-N-15，这些条带移动到2086、2091和2095 cm（-1），对于Hb-（CN）-C-13-N-14，这些条带移动到2073、2077和2081 cm（-1）。在KBr颗粒中的固体Hb-CN的红外光谱中已经确定了两个额外的谱带。峰在3.5和10.5之间的pH范围内持续存在，频率和强度变化较小。多个C-N伸缩带的出现与存在于不同环境中的C-N振子一致，并支持Hb-CN在所研究的条件下呈现多构象的假设。(C)2002 Elsevier Science B. V.保留所有权利。
Infrared spectra at 4 cm(-1) resolution of the cyanide ligated human methemoglobin (Hb-CN) were examined in the C-N stretching region. The FTIR spectra of hemoglobin ligated with the various isotopomeric forms of the cyanide ion support the existence of three conformational states for Hb-CN. In potassium phosphate buffer at pH of 7.5, the three bands were observed at 2116, 2122 and 2127 cm(-1) for natural abundance Hb-CN. These bands shift to 2086, 2091 and 2095 cm(-1) for Hb-(CN)-C-12-N-15 and 2073, 2077 and 2081 cm(-1) for Hb-(CN)-C-13-N-14. Two extra bands have been identified in the IR spectra of solid Hb-CN in KBr pellets. The peaks persist in the pH range between 3.5 and 10.5 with small changes in frequency and intensity. The appearance of several C-N stretching bands is consistent with C-N vibrators residing in different environment and support the hypothesis that Hb-CN assumes multiple conformers under the conditions studied. (C) 2002 Elsevier Science B.V. All rights reserved.