Interaction between fish myoglobin and myosin in vitro

Interaction between, tuna myoglobin and myosins from tuna and sardine was investigated in a model system at 4 degrees C for up to 24 h. Both sardine and tuna myosins bound progressively with tuna myoglobin as the storage time increased (P < 0.05). The soret absorption peak was noticeable in the myoglobin-myosin mixture. The oxidation of oxymyoglobin in the presence of myosin was generally greater than that found in the absence of myosin (P < 0.05). Oxymyoglobin underwent oxidation to a greater extent in the presence of tuna myosin than sardine myosin (P < 0.05). The interaction between fish myoglobin and myosin also caused changes in reactive sulfhydryl content and altered the tryptophan fluorescent intensity. The loss in Ca2+-ATPase activity of myosin varied with fish species and was governed by the myoglobin added. Thus, the interaction between fish myoglobin and myosin most likely occurred as a function of time and was species-specific. (c) 2006 Elsevier Ltd. All rights reserved.