Ferryl haem protonation gates peroxidatic reactivity in globins
Autor: | Peter Nicholls, Brandon J. Reeder, Chris E. Cooper, Michael T. Wilson, Radu Silaghi-Dumitrescu |
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Rok vydání: | 2007 |
Předmět: |
Chemistry
Stereochemistry Iron Optical transition Imidazoles Protonation Ascorbic Acid Cell Biology Hydrogen-Ion Concentration Biochemistry Hemoglobins chemistry.chemical_compound Peroxidases Myoglobin Spectrophotometry Animals Humans Reactivity (chemistry) Subarachnoid haemorrhage Globin Metmyoglobin Molecular Biology Research Article |
Zdroj: | Biochemical Journal. 403:391-395 |
ISSN: | 1470-8728 0264-6021 |
Popis: | Ferryl (Fe(IV)=O) species are involved in key enzymatic processes with direct biomedical relevance; among others, the uncontrolled reactivities of ferryl Mb (myoglobin) and Hb (haemoglobin) have been reported to be central to the pathology of rhabdomyolysis and subarachnoid haemorrhage. Rapid-scan stopped-flow methods have been used to monitor the spectra of the ferryl species in Mb and Hb as a function of pH. The ferryl forms of both proteins display an optical transition with pK∼4.7, and this is assigned to protonation of the ferryl species itself. We also demonstrate for the first time a direct correlation between Hb/Mb ferryl reactivity and ferryl protonation status, simultaneously informing on chemical mechanism and toxicity and with broader biochemical implications. |
Databáze: | OpenAIRE |
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