Binding of adenosine diphosphate to skeletal muscle myosin was studied using a range of concentrations from 0 to 2 mM. Up to 0.2 mM adenosine diphosphate two equivalent and independent nucleotide binding sites were detected, characterized by the single association constant of 5 x 104 M-1. At greater adenosine diphosphate concentrations a decreasing binding capacity was noticed, bound nucleotide being essentially ~ 0.1 mol/mol at a 1-2 mM adenosine diphosphate concentration. We tentatively propose that nucleotides act indirectly on myosin by promoting the perturbation of the solvent, which is supported by the fact that polyphosphates are known powerful kosmotropes.
Anomalous binding of MgADP to myosin of skeletal muscle
GRAZI, Enrico;
2000
Abstract
Binding of adenosine diphosphate to skeletal muscle myosin was studied using a range of concentrations from 0 to 2 mM. Up to 0.2 mM adenosine diphosphate two equivalent and independent nucleotide binding sites were detected, characterized by the single association constant of 5 x 104 M-1. At greater adenosine diphosphate concentrations a decreasing binding capacity was noticed, bound nucleotide being essentially ~ 0.1 mol/mol at a 1-2 mM adenosine diphosphate concentration. We tentatively propose that nucleotides act indirectly on myosin by promoting the perturbation of the solvent, which is supported by the fact that polyphosphates are known powerful kosmotropes.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
