Abstract
We prepared tilapia myosin rod by digesting myofibril with chymotrypsin. Subsequent digestion of the rod generated a 39 kDa light meromyosin (LMM), which could be isolated on DEAE-Toyopearl. The 39 kDa LMM had an isoelectric point of 5.5 higher than that of an ordinary LMM, 5.1. The 39 kDa LMM required no Mg2+ for its filament formation. These structural and filament forming proper ties of tilapia 39 kDa LMM are very similar to those of carp 40 kDa LMM. These similarities suggest that the tilapia 39 kDa LMM is derived from the carboxyl terminal end of the rodlike carp 40 kDa LMM. It was also found that the filament formed by tilapia 39 kDa LMM is more fragile than that by carp 40 kDa LMM. We therefore concluded that the filament forming ability of the39 KDa LMM is responsible for the fragile myosin filament of tilapia myosin.
