Modification of glyceraldehyde-3-phosphate dehydrogenase, EC, isolated from rainbow trout during acclimation at 5 or 15 degrees C--I. Changes in the activity of individual muscle isolates as evidence for variable adaptive responses.


The mean Km and Vmax values for G3PDH isolated from the lateral muscle of cold-adapted (5 degrees C) rainbow trout, Salmo gairdneri, were twice those of enzyme from warm-adapted (15 degrees C) trout when assayed at 7 degrees C but not at any other temperature. The entropy of activation of warm enzyme was about 3 times that of cold enzyme. However, enthalpy… (More)