Some molecular properties of muscle acylphosphatase

The molecular weight of acylphosphatase, purified from horse muscle, has been determined by gel filtration on Sephadex G-75 column; the method gave a value of about 10,000. The molecular weight of a minor component with acylphosphatase activity was determined by the same method, and a value of about 20,000 was obtained. The determination of the isoelectric point of the enzyme (major and minor component) was performed by thin-layer gel filtration electrophoresis on Sephadex G-75 Superfine. The values obtained were 11.4 and 11.6 for the major and the minor component, respectively. According to the above results, muscle acylphosphatase must be considered a basic protein with a low molecular weight.