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Is there a Root effect in Xenopus hemoglobin?

M Brunori·A Bellelli·B Giardina·S Condo·M F Perutz
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Abstract

The reaction of Xenopus hemoglobin with oxygen and carbon monoxide has been reinvestigated over the pH range 8.5-6.0, in the absence and presence of organic phosphates (2,3-diphosphoglycerate or inositol hexakisphosphate), to establish if the tetramer can be stabilized in a T-quaternary state by protons and polyphosphate; the equilibrium and kinetic data indicate that Xenopus hemoglobin does exhibit a Root effect. These new results are discussed with reference to those reported by Bridges et al. [(1985) Resp. Physiol. 61, 125-136] on Xenopus blood and, more generally, to the molecular definition and the structural basis of the Root effect as an extreme form of the Bohr effect.

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2,3-DiphosphoglycerateAnimalsCarbon MonoxideDiphosphoglyceric AcidsHemoglobinsHydrogen-Ion ConcentrationOxygenPhytic AcidXenopus laevisJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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M Brunori, A Bellelli, B Giardina, S Condo, M F Perutz. 1987-08-31. Is there a Root effect in Xenopus hemoglobin?. https://doi.org/10.1016/0014-5793(87)80372-1

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