Thermal Aggregation of Myosin Subfragments from Cod and Herring

Turbidity of fish myosin subfragment solutions increased with temperature, except cod heavy meromyosin turbidity leveled above 45°C. Extent of aggregation and number of cross-linking sites for cod heavy and light meromyosins were significantly higher than for herring (p<0.05), but only at temperatures above 35°C and 45°C, respectively. Thermal aggregation ability increased linearly with increased surface hydrophobicity (So) for the myosin subfragments, except cod heavy meromyosin where the increase in So between 45–55°C did not correspond to an increase in cross-linking ability. The lessened aggregation ability of herring myosins may be due to the low cross-linking of the HMM (S-2) region.