Identification of heme macrocycle type by near‐infrared magnetic circular dichroism spectroscopy at cryogenic temperatures

FEBS Letters

Peterson, Jim²  Loewen, Peter C.¹  Peng, Qinyun²  Timkovich, Russell² 

[1] Department of Microbiology, University of Manitoba, Winnipeg, Man, R3T 2N2, Canada;Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487-0336, USA

关键词: Electron paramagnetic resonance: Magnetic circular dichroism;    Catalase;    Hydroperoxidase;    Nitromyoglobin;    Chlorin;    Nitriheme;    EDTA;    ethylenediamineletraacetic acid;    EPR;    electron paramagnetic resonance;    HEPES;    N-(2-hydroxyethyl)piperazine-N′-(2-ethanesulfonic acid);    MCD;    magnetic circular dichroism;   

DOI  :  10.1016/0014-5793(92)81085-Z

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The electron paramagnetic resonance (EPR) and near-infrared magnetic circular dichroism (MCD) spectra of the azide and cyanide adducts of nitrimyoglobin and hydroperoxidase II from Escherichia coli have been measured at cryogenic temperatures. For the first time, ligand-to-metal charge-transfer transitions in the near-infrared have been observed for an Fe(III)-chlorin system. It is shown that near-ultraviolet-to-visible region electronic spectra of ‘green’ hemes such as these are an unreliable indicator of macrocycle type. However, the combined application of EPR and near-infrared MCD spectroscopics clearly distinguishes between the porphyrin-containing nitrimyoglobin and the chlorin-containing hydroperoxidase II.

【 授权许可】

Unknown