Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Buenos Aires, Argentina.
CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina.
J Inorg Biochem. 2021 Jul;220:111459. doi: 10.1016/j.jinorgbio.2021.111459. Epub 2021 Apr 20.
The reactivity of inorganic sulfide towards ferric bis(N-acetyl)- microperoxidase 11 in sodium dodecyl sulfate has been explored by means of visible absorption and resonance Raman spectroscopies. The reaction has been previously studied in buffered solutions at neutral pH and in the presence of excess sulfide, revealing the formation of a moderately stable hexacoordinated low spin ferric sulfide complex that yields the ferrous form in the hour's timescale. In the surfactant solution, instead, the ferrous form is rapidly formed. The spectroscopic characterization of the heme structure in the surfactant milieu revealed the stabilization of a major ferric mono-histidyl high spin heme, which may be ascribed to out of plane distortions prompting the detachment of the axially ligated water molecule, thus leading to a differential reactivity. The ferric bis(N-acetyl)- microperoxidase 11 in sodium dodecyl sulfate provides a model for pentacoordinated heme platforms with an imidazole-based ligand.
通过可见吸收和共振拉曼光谱研究了无机硫化物对十二烷基硫酸钠中双（N-乙酰基）-微过氧化物酶 11 的反应性。该反应先前在中性 pH 值的缓冲溶液中和在过量硫化物存在下进行了研究，揭示了形成中等稳定的六配位低自旋铁硫化物配合物，该配合物在小时尺度内生成亚铁形式。然而，在表面活性剂溶液中，亚铁形式迅速形成。在表面活性剂环境中对血红素结构的光谱表征表明，稳定了主要的铁单组氨酸高自旋血红素，这可能归因于平面外扭曲促使轴向配位的水分子脱落，从而导致不同的反应性。十二烷基硫酸钠中的双（N-乙酰基）-微过氧化物酶 11 为具有基于咪唑的配体的五配位血红素平台提供了模型。
