Hemoglobin Abruzzo (beta143 (H21) His replaced by Arg). Consequences of altering the 2,3-diphosphoglycerate binding site.

Published

Journal Article

Hemoglobin Abruzzo is an abnormal human hemoglobin with a substitution at a residue known to be involved in the binding of 2,3-diphosphoglyceric acid. It has increased oxygen affinity and reduced heme-heme interaction in the absence of organic or inorganic phosphate cofactors. In inorganic phosphate buffers the Bohr effect and heme-heme interaction are normal, but the oxygen affinity remains higher than that of hemoglobin A. CO combination in inorganic phosphate is more strongly autocatalytic than in normal hemoglobin and a slower rate of oxygen dissociation is observed. Although many of the functional differences of this variant may be attributed to the high oxygen affinity of the mutant beta chains, the interactions between subunits are also affected by the histidine to arginine substitution at beta143. Stripped hemoglobin Abruzzo appears to be significantly more dissociated than hemoglobin A. Kinetic studies indicate that interaction with organic or inorganic phosphates decreases its subunit dissociation. In all of the functional properties examined, hemoglobin Abruzzo is more sensitive to the allosteric influence of organic and inorganic anions than is hemoglobin A.

Full Text

Duke Authors

Cited Authors

  • Bonaventura, C; Bonaventura, J; Amiconi, G; Tentori, L; Brunori, M; Antonini, E

Published Date

  • August 1, 1975

Published In

Volume / Issue

  • 250 / 16

Start / End Page

  • 6273 - 6277

PubMed ID

  • 239943

Pubmed Central ID

  • 239943

Electronic International Standard Serial Number (EISSN)

  • 1083-351X

International Standard Serial Number (ISSN)

  • 0021-9258

Language

  • eng