TRANSGLUTAMINASE-INDUCED POLYMERIZATION OF A MIXTURE OF DIFFERENT FISH MYOSINS

This study was undertaken to investigate the effect of varying myosin ratios on covalent cross-linking of a mixture of two different myosins or actomyosins by transglutaminase from carp muscle. The progress of cross-linking of myosin heavy chains (MHC) of carp, rainbow trout, and atka mackerel was significantly different; carp MHC formed mainly dim er at a rate of 8 mu M . h(-1) . unit(-1), but rainbow trout and atka mackerel MHC formed dimer and large polymers (n greater than or equal to 3) at approximately the same rate of 55 mu M . h(-1) . unit(-1). Th e cross-linking rate of MHC in mixed myosins of carp and rainbow trout increased with increasing ratio of rainbow trout to carp. On the othe r hand, in the case of a mixture of rainbow trout and atka mackerel, t he MHC in mixed actomyosins at any ratio were cross-linked to form lar ge polymers at the same rate, suggesting the formation of co-polymers with each other.