Studies on scapharca hemoglobins. Properties of the dimeric protein reconstituted with Fe- or Co-porphyrin

D. Verzili, R. Santucci, M. Ikeda-saito, E. Chiancone, F. Ascoli, T. Yonetani, E. Antonini

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

A native globin from the dimeric hemoglobin, hemoglobin I, of the mollusc Scapharca inaequivalvis has been obtained with the acid-acetone method. The globin has a lower sedimentation coefficient than the native protein at neutral pH; its reconstitution product with natural heme has the same physicochemical and functional properties as the native protein, proto- and meso-cobalt hemoglobin I have been prepared and characterized, proto-Cobalt hemoglobin I binds oxygen reversibly with a lower affinity and a lower cooperativity than native hemoglobin I; thus, the changes in the functional properties brought about by substitution of iron with cobalt are similar to those observed in human hemoglobin A. The EPR spectra of deoxy-proto-cobalt hemoglobin I and of the photolysis product of oxy-meso-cobalt hemoglobin I indicate that two histidine residues are the apical heme ligands. The broad signal at g = 2.38 in deoxy-proto-cobalt hemoglobin I points to a constrained structure of the heme site in this derivative which results from a distorted coordination of the hindered proximal histidine. A similar structure has been proposed previously for the α chains in deoxy-cobalt hemoglobin A.

Original languageEnglish
Pages (from-to)215-220
Number of pages6
JournalBiochimica et Biophysica Acta (BBA)/Protein Structure and Molecular
Volume704
Issue number2
DOIs
Publication statusPublished - 1982 Jun 4

Keywords

  • (Scapharca)
  • Fe-porphyrin
  • Hemoglobin
  • Metalloprotein
  • Reconstituted dimer

ASJC Scopus subject areas

  • Biophysics
  • Structural Biology
  • Biochemistry
  • Molecular Biology

Fingerprint Dive into the research topics of 'Studies on scapharca hemoglobins. Properties of the dimeric protein reconstituted with Fe- or Co-porphyrin'. Together they form a unique fingerprint.

Cite this