Hoy G R, Cook D C, Berger R L, Friedman F K
Biophys J. 1986 May;49(5):1009-15. doi: 10.1016/S0006-3495(86)83729-8.
Samples of 90% enriched 57Fe hemoglobin and its isolated subunits have been prepared. Mössbauer spectroscopic measurements have been made on three such samples. Sample one contained contributions of oxyhemoglobin, deoxyhemoglobin, and carbonmonoxyhemoglobin. This sample was studied from a temperature of 90 K down to 230 mK. Measurements were also made at 4.2 K using a small applied magnetic field of 1.0 T. In general, the measured quadrupole splittings and isomer shifts for each component agreed with previous measurements on single component samples in the literature, and thus demonstrated that chemically enriched hemoglobin has not been altered. The second and third samples were isolated alpha and beta subunits, respectively. We have found measurable Mössbauer spectral differences between the HbO2 sites in the alpha subunit sample and the beta subunit sample. The measured Mössbauer spectral areas indicate that the iron ion has the largest mean-square displacement at the deoxy Hb sites as compared to that at the oxy- and carbonmonoxy Hb sites. The mean-square displacement at the HbO2 sites is the smallest.
已制备出90%富集的57Fe血红蛋白及其分离亚基的样品。已对三个这样的样品进行了穆斯堡尔光谱测量。样品一包含氧合血红蛋白、脱氧血红蛋白和碳氧血红蛋白的成分。该样品从90 K的温度研究到230 mK。还在4.2 K下使用1.0 T的小外加磁场进行了测量。总体而言，对每个成分测量的四极分裂和同质异能位移与文献中对单成分样品的先前测量结果一致，因此表明化学富集的血红蛋白未发生改变。第二个和第三个样品分别是分离的α亚基和β亚基。我们发现α亚基样品和β亚基样品中HbO2位点之间存在可测量的穆斯堡尔光谱差异。测量的穆斯堡尔光谱面积表明，与氧合血红蛋白和碳氧血红蛋白位点相比，铁离子在脱氧血红蛋白位点的均方位移最大。在HbO2位点的均方位移最小。
