Open AccessDirect Measurement of the pK Values of an Alkaline Bohr Group in Human Hemoglobin
Author(s) -
John V. Kilmartin,
J. J. Breen,
Gordon C. K. Roberts,
Chien Ho
Publication year - 1973
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.70.4.1246
Subject(s) - bohr effect , histidine , hemoglobin , chemistry , nuclear magnetic resonance , resonance (particle physics) , proton , biochemistry , enzyme , physics , atomic physics , quantum mechanics , oxygen–haemoglobin dissociation curve
Proton nuclear magnetic resonance spectra of normal and des-(his 146β) human hemoglobin in the aromatic resonance region have been compared at different pH values. From these measurements, a pK value for histidine 146β of 7.1 in carbonmonoxyhemoglobin and 8.0 in deoxyhemoglobin has been found. These pK values confirm the proposed role of histidine 146β in the alkaline Bohr effect.