Visible region MCD and MLD spectra of nitrosylferrohemoglobin and oxyhemoglobin.
Visible region MCD and MLD spectra of nitrosylferrohemoglobin and oxyhemoglobin.
复制标题
亚硝基铁血红蛋白和氧合血红蛋白的可见区 MCD 和 MLD 光谱。
DOI：
10.1016/s0006-291x(02)02153-8
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发表时间：
2002
影响因子：
3.1
通讯作者：
Peterson,Jim
中科院分区：
文献类型：
--
作者：
Pearce,LindaL;Bominaar,EmileL;Peterson,Jim
利用磁性圆二色性（MCD）和磁性线性二色性（MLD）光谱，研究了不同磁场（0- 6 T）和温度（2.0- 31 K）下氧合和亚硝基铁血红蛋白（HbNO）可见光区（Q 0 -0，或α带）的电子性质。d 6（S=0）双磁体OxyHb在574 nm处具有预期的伪一阶导数MCD和伪二阶导数MLD温度无关特性。d 7（S=1/2）顺磁体HbNO也具有与温度无关的伪一阶导数MCD谱，但其中心波长为571 nm。据我们所知，这种行为在顺磁性铁卟啉的MCD谱中是前所未有的，预计顺磁性铁卟啉的MCD谱将由温度依赖性C 0项主导。然而，HbNO MCD谱确实证明了有限的场依赖性饱和磁化行为，并且MLD谱目前低于检测限。此外，MCD信号从再氧静脉血的报告和MCD信号从氧和HbNO衍生物相比。最后，结合MCD和MLD谱估计了oxyHb α带激发态的轨道角动量（ML）值为4.2（±0.7）。
Magnetic circular dichroism (MCD) and magnetic linear dichroism (MLD) spectroscopies at various applied magnetic fields (0–6T) and temperatures (2.0–31K) have been used to investigate the electronic properties of the visible (Q0–0, or α band) region of oxy- and nitrosylferrohemoglobin (HbNO). OxyHb, a d6(S=0) diamagnet, exhibits the expected pseudo-first derivative MCD and pseudo-second derivative MLD temperature-independent features centered at 574nm. HbNO, a d7(S=1/2) paramagnet, also exhibits a temperature-independent pseudo-first derivative MCD spectrum, but centered at 571nm. So far as we are aware, this behavior is unprecedented in the MCD spectra of paramagetic iron-porphyrins, which are expected to be dominated by temperature-dependent C0terms. The HbNO MCD spectrum does, however, demonstrate limited field-dependent saturation magnetization behavior and the MLD spectrum is currently below the detection limit. In addition, an MCD signal from reoxygenated venous blood is reported and compared with MCD signals from oxy- and HbNO derivatives. Finally, a combination of MCD and MLD spectroscopies has been used to estimate the orbital angular momentum (ML) value of the α band excited state of oxyHb as 4.2 (±0.7).