Hydration-dependent conformational states of hemoglobin. Equilibrium and kinetic behavior
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Data
1990-07-27
Autores
Colombo, M. F.
Sanches, R. [UNESP]
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Resumo
The equilibrium and kinetics of methemoglobin conversion to hemichrome induced by dehydration were investigated by visible absorption spectroscopy. Below about 0.20 g water per g hemoglobin only hemichrome was present in the sample; above this value, an increasing proportion of methemoglobin appeared with the increase in hydration. The transition between the two derivatives showed a time-dependent biphasic behavior and was observed to be reversible. The rates obtained for the transition of methemoglobin to hemichrome were 0.31 and 1.93 min-1 and for hemichrome to methemoglobin 0.05 and 0.47 min-1. We suggest that hemichrome is a reversible conformational state of hemoglobin and that the two rates observed for the transition between the two derivatives reflect the α- and β-chains of hemoglobin.
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Conformational state, Hemichrome, Hemoglobin, Hydration, hemoglobin, hemichrome, priority journal, protein conformation, Desiccation, Hemeproteins, Human, Kinetics, Methemoglobin, Protein Conformation, Spectrophotometry, Support, Non-U.S. Gov't, Water
Como citar
Biophysical Chemistry, v. 36, n. 1, p. 33-39, 1990.