Occurrence and formation of endogenous histidine hexa-coordination in cold-adapted hemoglobins(467 views) Merlino A, Howes BD, Prisco G, Verde C, Smulevich G, Mazzarella L, Vergara A
Iubmb Life (ISSN: 1521-6543, 1521-6551), 2011 May; 63(5): 295-303.
Keywords: Crystallography, Epr, Hemichrome, Quaternary Structure, Resonance Raman, Root Effect, Hemoglobin, Histidine, Unclassified Drug, Antarctic Fish, Nonhuman, Protein Function, Protein Stability, Protein Structure, Review, Spectroscopy, Stereochemistry, Adaptation, Biological, Animals, Cold Temperature, X-Ray, Hemeproteins, Iron, Models, Molecular, Oxidation-Reduction, Protein Conformation, Genetics,
Affiliations: *** IBB - CNR ***
Department of Chemistry Paolo Corradini, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cinthia, I-8012 Naples, Italy
Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, I-80134 Naples, Italy
Dipartimento di Chimica Ugo Schiff, Università di Firenze, Via della Lastruccia 3-13, I-50019 Sesto Fiorentino (FI), Italy
Institute of Protein Biochemistry, CNR, Via Pietro Castellino 111, I-80131 Naples, Italy
References: Not available.
Occurrence and formation of endogenous histidine hexa-coordination in cold-adapted hemoglobins
Spectroscopic and crystallographic evidence of endogenous (His) ligation at the sixth coordination site of the heme iron has been reported for monomeric, dimeric, and tetrameric hemoglobins (Hbs) in both ferrous (hemochrome) and ferric (hemichrome) oxidation states. In particular, the ferric bis-histidyl adduct represents a common accessible ordered state for the beta chains of all tetrameric Hbs isolated from Antarctic and sub-Antarctic fish. Indeed, the crystal structures of known tetrameric Hbs in the bis-His state are characterized by a different binding state of the alpha and beta chains. An overall analysis of the bis-histidyl adduct of globin structures deposited in the Protein Data Bank reveals a marked difference between hemichromes in tetrameric Hbs compared to monomeric/dimeric Hbs. Herein, we review the structural, spectroscopic and stability features of hemichromes in tetrameric Antarctic fish Hbs. The role of bis-histidyl adducts is also addressed in a more evolutionary context alongside the concept of its potential physiological role. (C) 2011 IUBMB IUBMB Life, 63 (5): 295-303, 2011
Occurrence and formation of endogenous histidine hexa-coordination in cold-adapted hemoglobins