title: Whole blood-oxygen binding properties of four cold-temperate marine fishes: blood affinity is independent of pH-dependent binding, routine swimming performance, and environmental hypoxia.
abstract: The relationship between whole blood-oxygen affinity (P(50)) and pH-dependent binding (i.e., cooperativity and the Bohr [ Phi ] and Root effects) was examined statistically under standardized conditions (10.0 degrees Celsius) in four unrelated cold-temperate marine fishes that differ widely in their swimming performance and their expected responses to hypoxia: cod (Gadus morhua), herring (Clupea harengus), mackerel (Scomber scombrus), and plaice (Pleuronectes platessa). An unexpected difference in blood-oxygen affinity was found (herring>plaice>mackerel>cod), and this was independent of both swimming performance and the predicted low O(2) response of each species. The ecotype of the four marine species was also unrelated to pH-dependent binding because no difference in the Bohr effect was apparent ( Phi varied insignificantly from -0.90 to -1.06), and differences in the magnitude of the cooperative binding reaction were associated only with the presence of the Root effect. Although several reviews propose a generalized link between blood-oxygen affinity and pH-dependent binding, our results advise against overestimating the adaptive functional properties of hemoglobin across unrelated species.
authors.affiliation: Marine Biological Laboratory, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark. n.herbert@bio.gla.ac.uk
authors.forename: Neill A
authors.initials: NA
authors.lastname: Herbert
authors.forename: Peter V
authors.initials: PV
authors.lastname: Skov
authors.forename: Rufus M G
authors.initials: RM
authors.lastname: Wells
authors.forename: John F
authors.initials: JF
authors.lastname: Steffensen
mesh_terms: D000818:Animals; D003080:Cold Temperature; D017753:Ecosystem; D005399:Fishes / Q000097:blood* / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D009792:Oceans and Seas; D010100:Oxygen / Q000097:blood* / Q000378:metabolism*; D013550:Swimming / Q000502:physiology*
chemical_list: D010100:Oxygen