title: Tertiary and quaternary effects in the allosteric regulation of animal hemoglobins.
abstract: In the last decade, protein allostery has experienced a major resurgence, boosted by the extension of the concept to systems of increasing complexity and by its exploitation for the development of drugs. Expansion of the field into new directions has not diminished the key role of hemoglobin as a test molecule for theory and experimental validation of allosteric models. Indeed, the diffusion of hemoglobins in all kingdoms of life and the variety of functions and of quaternary assemblies based on a common tertiary fold indicate that this superfamily of proteins is ideally suited for investigating the physical and molecular basis of allostery and firmly maintains its role as a main player in the field. This review is an attempt to briefly recollect common and different strategies adopted by metazoan hemoglobins, from monomeric molecules to giant complexes, exploiting homotropic and heterotropic allostery to increase their functional dynamic range. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins.
authors.affiliation: Department of Pharmacy, University of Parma, Parco Area delle Scienze 23/A, Parma, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Ronda
authors.forename: Stefano
authors.initials: S
authors.lastname: Bruno
authors.forename: Stefano
authors.initials: S
authors.lastname: Bettati
mesh_terms: D000494:Allosteric Regulation; D000818:Animals; D006454:Hemoglobins / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D010100:Oxygen / Q000378:metabolism*; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary
chemical_list: D006454:Hemoglobins; D010100:Oxygen
keywords: Allostery; Cooperative oxygen binding; G protein-coupled receptors; GPCRs; Giant hemoglobin; Hb; Heterotropic effectors; IHP; KNF; Koshland, Nemethy and Filmer; MWC; Mb; Microspectrophotometry; Monod, Wyman and Changeux; Ngb; TTS; Tertiary two-state model; hemoglobin; inositol haxaphosphate; myoglobin; neuroglobin; tertiary two-state allosteric model