Nienhaus Karin, Nienhaus Gerd U
Department of Biophysics, University of Ulm, Ulm 89069, Germany.
Micron. 2004;35(1-2):67-9. doi: 10.1016/j.micron.2003.10.014.
Using Fourier Transform Infrared Spectroscopy at cryogenic temperatures, we have studied carbon monoxide (CO) migration in the interior of sperm whale myoglobin and binding to teh heme iron. The effect of protein internal cavities was examined by comparing the wild-type protein with mutants in which the cavities were blocked by bulky amino acid sidechains. After photodissociation at 3 K, CO ligands reside in the primary docking site (B) from where they can migrate to other sites (C, D) that were identified as the Xe4 and Xe1 cavities. These studies were complemented by flash photolysis experiments at room temperature, which revealed that the protein cavities enable efficient excape of ligands from the protein after dissociation from the heme iron.
在低温下使用傅里叶变换红外光谱，我们研究了一氧化碳（CO）在抹香鲸肌红蛋白内部的迁移以及与血红素铁的结合。通过将野生型蛋白与其中腔被庞大氨基酸侧链阻断的突变体进行比较，研究了蛋白质内部空腔的影响。在3K下光解离后，CO配体位于主要对接位点（B），从那里它们可以迁移到被确定为Xe4和Xe1空腔的其他位点（C、D）。这些研究通过室温下的闪光光解实验得到补充，该实验表明蛋白质空腔能够使配体在从血红素铁解离后有效地从蛋白质中逸出。
