The Soret magnetic circular dichroism of ferric high‐spin myoglobins: A probe for the distal histidine residue

Ariki MATSUOKA, Nagao KOBAYASHI, Keiji SHIKAMA

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

To find a simple criterion for the presence of the distal (E7) histidine residue in myoglobins and hemoglobins, the Soret magnetic‐circular‐dichroic spectra were examined for ferric metmyoglobins from various species. A distinct and symmetric dispersion‐type curve was obtained for myoglobins containing the distal histidine, whereas a relatively weak and unsymmetric pattern was observed for myoglobins lacking this residue, such as those from three kinds of gastropodic sea molluscs, a shark and the African elephant. The magnetic‐circular‐dichroic spectra obtained would thus be a direct reflection of the presence or absence of a water molecule at the sixth coordinate position of the heme iron(III), this axial water ligand being stabilized by hydrogen‐bond formation to the distal histidine residue. On the basis of these Soret magnetic‐circular‐dichroic signals, we also examined the structure of a protozoan myoglobin (or a monomeric hemoglobin) from Paramecium caudatum of particular interest for the evolution of these proteins from protozoa to higher animals.

Original languageEnglish
Pages (from-to)337-341
Number of pages5
JournalEuropean Journal of Biochemistry
Volume210
Issue number1
DOIs
Publication statusPublished - 1992 Nov

ASJC Scopus subject areas

  • Biochemistry

Fingerprint Dive into the research topics of 'The Soret magnetic circular dichroism of ferric high‐spin myoglobins: A probe for the distal histidine residue'. Together they form a unique fingerprint.

  • Cite this