Preparation of Troponin and Its Subnits

This chapter presents procedure for preparation of troponin and its subnits. The procedures presented are for both skeletal and cardiac muscle. Although there are significant differences between the purification procedures for the cardiac and skeletal troponins, the same basic procedures are employed. The first step consists of making an ether powder (procedure is identical for both cardiac and skeletal muscle), followed by an high ionic strength extraction and initial fractionation of troponin. This partially purified troponin, called crude troponin, can be further purified to yield pure troponin using Cibacron Blue-Sephacryl chromatography similar to the Cibacron Blue-agarose chromatography procedure. The crude troponin can also be used to prepare pure troponin subunits by various combinations of chromatography on DEAE-Sephadex and CM-Sephadex in the presence of 6 M urea and 1 mM EDTA.