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PubMed · 7256263

Structural changes at the heme induced by freezing hemoglobin.

M R Ondrias·D L Rousseau·S R Simon
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Abstract

A dramatic change occurs in the vibrational properties of the iron-histidine bond, trans to the oxygen binding site, on freezing deoxyhemoglobin. The large, quaternary structure-dependent differences in the shape and frequency of the iron-histidine mode observed in resonance Raman scattering measurements above freezing ae significantly diminished by the freezing event and the scattering intensity increases substantially. On further reduction in temperature to 10 K this broad line becomes narrow and shifts to a higher frequency. These data implicate dynamical processes and protein interaction with water as contributors to the quaternary structure dependence of the iron-histidine bond and thus reflect on the role of that bond in the energetics of cooperative ligand binding.

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Allosteric RegulationFreezingHemeHemoglobin AHistidineHumansMotionProtein ConformationSpectrum Analysis, RamanWaterJournal Article

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M R Ondrias, D L Rousseau, S R Simon. 1981-08-07. Structural changes at the heme induced by freezing hemoglobin.. https://doi.org/10.1126/science.7256263

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