Effect of synthetic Lys-Trp on adenosine triphosphatase activity of carp and rabbit myosin Bs

1. With carp myosin B ATPase, the acceleration effect was found at peptide concentration ranging between 1 nM and 1 mM with a maximum at 10 nM (30% acceleration) at the low myosin B concentration (0.2 mg/ml). At the high myosin B concentration (0.8 mg/ml) a maximum was observed at 1-10 mM (10% acceleration). 2. With rabbit myosin B ATPase, the acceleration (10%) was found only at a microM of Lys-Trp in the case of low myosin B concentration (0.2 mg/ml). Under the high concentration of rabbit myosin B, a maximum acceleration (150%) was found at 5 mM of the synthetic Lys-Trp. 3. Effect on superprecipitation was tested only at the high concentration of rabbit myosin B (0.8 mg/ml). The acceleration increased with increasing concentration of Lys-Trp up to 10 mM.