Myoglobin oxygen dissociation by multiwavelength spectroscopy
Myoglobin oxygen dissociation by multiwavelength spectroscopy
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DOI：
10.1152/jappl.1997.82.1.86
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发表时间：
1997-01-01
影响因子：
3.3
通讯作者：
Feigl, EO
中科院分区：
文献类型：
--
作者：
Schenkman, KA;Marble, DR;Feigl, EO
采用多波长光谱法研究了马肌红蛋白的氧结合特性。氧结合关系作为氧张力的函数，在10，25，35，37和40摄氏度的温度下，在pH 7.0下测定。此外，在37 ° C下测定pH 6.5：7.0和7.5的解离曲线。在所需的温度和pH下，用肌红蛋白溶液和已知氧分数的16种氧-氮气混合物实现平衡。通过使用三组分最小二乘法分析和通过校正终点氧肌红蛋白光谱中高铁肌红蛋白的存在来校正不可避免的高铁肌红蛋白的存在。在pH 7.0和37 ℃下，肌红蛋白被O-2（P-50）半饱和时的PO 2被确定为2.39 Torr。肌红蛋白解离曲线符合Hill方程[饱和度= PO 2/（PO 2 + P-50）]。
Multiwavelength optical spectroscopy was used to determine the oxygen-binding characteristics for equine myoglobin. Oxygen-binding relationships as a function of oxygen tension were deter mined for temperatures of 10, 25, 35, 37, and 40 degrees C, at pH 7.0. In addition, dissociation curves were determined at 37 degrees C for pH 6.5: 7.0, and 7.5. Equilibration was achieved with a myoglobin solution, at the desired temperature and pH, and 16 oxygen-nitrogen gas mixtures of known oxygen fraction. Correction for the inevitable presence of metmyoglobin was made by using a three-component least squares analysis and by correcting the end point oxymyoglobin spectra for the presence of metmyoglobin. The PO2 at which myoglobin is half-saturated with O-2(P-50) was determined to be 2.39 Torr at pH 7.0 and 37 degrees C. The myoglobin dissociation curve was well fit: by the Hill equation [saturation = PO2/(PO2 + P-50)].