Myoglobin (Mb) is an oxygen binding protein found in vertebrate skeletal muscle where it facilitates intracellular transport and storage of oxygen. This protein has evolved to suit unique physiological needs in the muscle of diving vertebrates that express Mb at much greater concentrations than their terrestrial counterparts. In this study, we characterized Mb oxygen affinity (P50) from 25 species of aquatic and terrestrial birds and mammals. Among diving species we tested for correlations between Mb P50 and routine dive duration. Across all species examined, Mb P50 ranged from 2.40–4.85 mmHg. The mean P50 of Mb from terrestrial ungulates was 3.72±0.15 mmHg (range 3.70–3.74 mmHg). The P50 of cetaceans was similar to terrestrial ungulates ranging from 3.54–3.82 mmHg with the exception of the melon-headed whale that had a significantly higher P50 of 4.85 mmHg. Among pinnipeds, the P50 ranged from 3.23–3.81 mmHg and showed a trend for higher oxygen affinity in species with longer dive durations. Among diving birds, the P50 ranged from 2.40–3.36 mmHg and also showed a trend of higher affinities in species with longer dive durations. In pinnipeds and birds, low Mb P50 was associated with species whose muscles are metabolically active under hypoxic conditions associated with aerobic dives. Given the broad range of potential globin oxygen affinities, Mb P50 from diverse vertebrate species appears constrained within a relatively narrow range. High Mb oxygen affinity within this range may be adaptive for some vertebrates that make prolonged dives.
Myoglobin oxygen affinity in aquatic and terrestrial birds and mammals
Currently Viewing Accepted Manuscript - Newer Version Available
Traver J. Wright, Randall W. Davis; Myoglobin oxygen affinity in aquatic and terrestrial birds and mammals. J Exp Biol 2015; jeb.119321. doi: https://doi.org/10.1242/jeb.119321
Download citation file:
Advertisement
2023 JEB Outstanding Paper Prize shortlist and winner
The JEB Editors are delighted to announce the shortlisted authors for the 2023 JEB Outstanding Paper Prize. Read the winning paper - Tiny spies: mosquito antennae are sensitive sensors for eavesdropping on frog calls - by Hoover Pantoja-Sanchez and Brian Leavell from Ximena Bernal's lab at Purdue University, USA.
JEB Science Communication Workshop for ECRs
If you’re an early-career researcher interested in science communication and are attending the SEB Annual Conference in Prague this summer, come a day early and join the JEB Editors at a sci comm workshop to learn the key writing skills needed to promote your research to a broad audience beyond your peers (1 July at 14.30-17.30). Places are limited to 24 attendees, and applicants should apply through the SEB registration page by 30 April 2024.
Bridging the gap between controlled conditions and natural habitats in understanding behaviour
Novel technologies enable behavioural experiments with non-model species, in naturalistic habitats and with underexplored behaviours. In their Commentary, Scholz and colleagues discuss how to obtain a deeper understanding of the natural ecology and lifestyle of study animals.
How a macrourid fish remains buoyant at depths it should be unable to reach
Fish with swimbladders should not be capable of descending below 7200m, but when Alan Jamieson and Todd Bond spotted a macrourid fish at 7259m, they knew they had seen something miraculous. Working with Imantes Priede, they reveal that the swimbladder of a 1 kg fish could hold 37.9 g of oxygen, sufficient to offset the weight of the fish's bones, and take 221-440 days to fill, which is plausible because it takes years for the fish to descend to such depths.
ECR Workshop on Positive Peer Review
Are you an ECR looking for tips on how to write concise, astute and useful manuscript reviews? If so, join the JEB Editors at a 2-hour JEB-sponsored Workshop on Positive Peer Review at the Canadian Society of Zoologists annual meeting in Moncton on 9 May 2024 at 13.00-15.00. There are 25 spaces for ECRs and selection is first come, first serve. To sign up, check the ECR Workshop box when you register for the CSZ meeting.