Further observations on the chromatography of myosin preparations on hydroxyapatite.

An improved procedure for a high ionic strength chromatographic fractionation of myosin preparations on hydroxyapatite was developed and applied to crude preparations of myosin made from fresh and aged bovine and rabbit muscles, and to a preparation containing both sarcoplasmic and myofibrillar proteins made from fresh rabbit muscle. The efficiency of the procedure in removing actin and other contaminating proteins from myosin was demonstrated. The results also indicate that the methods would be useful in a study of the compositional changes in muscle on aging.