Purification of rabbit skeletal muscle troponin C.

Troponin C binds to phenyl-Sepharose in the presence of Ca2+ and can be eluted with EDTA. This property was used as an essential step in the purification of this protein from rabbit skeletal muscle. Troponin C was extracted with 6M urea from extensively washed ground muscle. The protein was bound to and eluted from DEAE-Sephadex, fractionated by size on Sephadex G75, and in a final step purified from UV-absorbing non-protein impurities on phenyl-Sepharose. The total yield of electrophoretically pure protein was 60 mg per 100 g of muscle, which is considerably higher than that previously obtained.