ARE CHANGES IN ENZYME-ACTIVITIES OF FISH MUSCLE DURING COLD-ACCLIMATION SIGNIFICANT

An equation similar to the one used to obtain Q(10) values can be used to estimate the significance of an increase in the activity of aerobi c enzymes in cold-acclimated fish. The phenomenon of increased activit y of mitochondrial enzymes in cold-acclimated fish is surveyed using d ata from published studies, and whether or not this increase can count eract the limiting effects of low temperatures on the rate of reaction s implicated in oxidative phosphorylation is investigated. It is concl uded that the significance of an increase in enzyme content can vary w ith species. In some studies, data indicate an almost perfect compensa tion, while in other cases an imperfect compensation is found in the r ate of chemical reactions after cold acclimation It is suggested that the range of temperature difference between the cold- and warm-acclima ted fish does not always influence the magnitude of the response exhib ited in cold-acclimated fish.