Modification of glyceraldehyde-3-phosphate dehydrogenase, EC 1.2.1.12, 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 or free energy of activation among acclimation groups differed less or not at all. Individual G3PDH isolates within either adaptation group differed in kinetic characteristics.
D000064:Acclimatization; D000818:Animals; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D009132:Muscles / Q000201:enzymology*; D012487:Salmonidae / Q000502:physiology*; D013696:Temperature; D013816:Thermodynamics; D014337:Trout / Q000502:physiology*
D005987:Glyceraldehyde-3-Phosphate Dehydrogenases