Journal article
Iron ligand recognition by monomeric hemoglobins
Biochimica et biophysica acta, Protein structure and molecular enzymology, v 1295(2)
1996
PMID: 8695648
Featured in Collection : UN Sustainable Development Goals @ Drexel
Abstract
Binding affinities of monomeric
Glycera dibranchiata hemoglobin for some anions and heterocyclic amines, including imidazoles, pyrazole, triazole and tetrazole have been evaluated and compared with those of sperm whale and horse heart myoglobin. The proteins' affinities for substituted heterocyclic amines are strongly influenced by the steric bulk and flexibility of the aromatic ring. The ligand coordination mode depends on the heme oxidation state, iron(III) amine adducts being more stable than the iron(II) adducts, the higher affinities of stronger Brønsted-Lowry bases reflecting their essentially σ-donor character. The bifunctional molecule morpholinoethylisocyanide acts as a redox-state-dependent ambidentate ligand, binding as an N-donor to iron(III), but as a C-donor to iron(II). pH-Dependences of the ESR and optical spectra of the azole adducts reveal iron-linked ionisations and spin-equilibria in the heme pocket. Enthalpy and entropy changes for the binding process were estimated for several ligands, and mutually compensatory behaviour is observed globally for
ΔH° and
ΔS°. At the compensation temperature θ, the binding affinities of monomeric
Glycera dibranchiata hemoglobin and sperm whale myoglobin are similar and associated with free energy changes
ΔG°(
θ) ≈ −9 ± 1 kJ mol
−1 for the heterocyclic and anionic ligands.
Metrics
Details
- Title
- Iron ligand recognition by monomeric hemoglobins
- Creators
- Joseph J. Stephanos - Menoufia UniversityScott A. Farina - Drexel UniversityAnthony W. Addison - Drexel University
- Publication Details
- Biochimica et biophysica acta, Protein structure and molecular enzymology, v 1295(2)
- Publisher
- Elsevier
- Resource Type
- Journal article
- Language
- English
- Academic Unit
- Chemistry
- Web of Science ID
- WOS:A1996UY02400012
- Scopus ID
- 2-s2.0-0030592151
- Other Identifier
- 991019169622804721
UN Sustainable Development Goals (SDGs)
This publication has contributed to the advancement of the following goals:
InCites Highlights
Data related to this publication, from InCites Benchmarking & Analytics tool:
- Collaboration types
- Domestic collaboration
- International collaboration
- Web of Science research areas
- Biochemistry & Molecular Biology
- Biophysics