Jim Ballantyne

Jim Ballantyne
Professor Emeritus

My interest in aquatic organisms began at an early age as I grew up fishing on the Rideau River system in Ontario. This was reinforced and focused in my undergraduate and graduate degrees where I developed my interests in physiology and biochemistry. My Ph.D. at the University of British Columbia with Peter Hochachka fixed my interests in the mechanisms of biochemical adaptation. My current research examines the biochemistry of aquatic organisms in both an adaptive and an evolutionary context.

  • BSc Guelph 1973
  • MSc Guelph 1976
  • PhD British Columbia 1981

Environmental Adaptation

We are interested in how teleost and elasmobranch fishes adapt to different salinities. These studies involve examination of membrane lipid and transporters as well as solute changes. Changes in metabolic pathways, particularly those involving nitrogen compounds are being investigated using 15N labelled compounds.

The membrane and metabolic alterations during metabolic arrest in terrestrial snails and African lungfish are also of interest since these organisms undergo a reduction in metabolism at a constant temperature (estivation). This allows us to more easily define the changes associated with metabolic arrest compared to animal hibernation models where temperature is also a variable.

Comparative and Evolutionary Aspects of Metabolism

Mollusc Metabolism

Some metabolic pathways seem to map more closely to environmental conditions that to phylogenetic relations. In particular, ketone body metabolism of molluscs is of interest. We have shown that while terrestrial and freshwater molluscs have a well developed ketone body metabolism, marine molluscs do not express the terminal enzyme in the pathway (β-hydroxybutyrate dehydrogenase).

Elasmobranch Metabolism

The metabolism of elasmobranch fishes differs substantially from that of virtually all other vertebrates due to the need to synthesize substantial amounts of urea for osmotic support. This need changes when elasmobranches enter freshwater. We have examined the metabolic changes associated with salinity challenge in elasmobranches. Current research is focused on some of the factors associated with disease resistance in elasmobranches.

  • Ballantyne, J. S. and Fraser, D. I. (2013). Euryhaline elasmobranchs. In: Euryhaline Fishes. Fish Physiology Volume 32 (eds. McCormick, S. D., Farrell, A. P., and Brauner, C. J.), pp. 125-198. Amsterdam: Academic Press.
  • Ballantyne, J. S. (2013). Membranes and metabolism of fishes. In: The physiology of fishes (ed. Evans, D. H.), CRC Press.
  • Fraser, D. I. and Ballantyne, J. S. (2013). Freshwater elasmobranchs: why so few species. Shark Focus Issue 46 March 2013, 4-5.
  • Robinson, J. W., Yanke, D., and Ballantyne, J. S. (2013). Plasma free amino acid kinetics in a shark (Squalus acanthias) using bolus injections of 15N labelled amino acids. Amino Acids.
  • Ballantyne, J. S. and Frick, N. T. (2011). Lungfish metabolism. In: Lungfish Biology pp. 301-335. Boca Raton: CRC Press.
  • Ballantyne, J. S. and Robinson, J. W. (2011). Physiology of sharks, skates and rays. In: Encyclopedia of fish physiology: from genome to environment. Volume 3 (ed. Farrell, A. P.), pp. 1807-1818. San Diego: Academic Press.
  • Robinson, J. W. et al. (2011). Plasma free amino acid kinetics in rainbow trout (Oncorhynchus mykiss) using a bolus injection of 15N-labelled amino acids. Amino Acids 40, 689-696.
  • Ballantyne, J. S. and Robinson, J. W. (2010). Freshwater elasmobranchs: a review of their physiology and biochemistry. J. Comp. Physiol. 180B, 475-493.
  • Frick, N. T. et al. (2010). Cytochrome c oxidase is regulated by modulations in protein expression and mitochondrial membrane phospholipid composition in estivating African lungfish. Am. J. Physiol. 298, R608-R616.
  • Robinson, J. W. et al. (2010). The metabolic fate of intraperitoneally injected 15N ammonium chloride in a marine elasmobranch, Taeniura lymma. Physiol. Biochem. Zool.
  • IBIO*4010 Adaptational Physiology
  • ZOO*4300 Marine Biology and Oceanography
  • ZOO*4540 Marine and Freshwater Research I