The C-proteins of rabbit red, white, and cardiac muscles.

摘要: C-proteins have been isolated from rabbit red skeletal muscle (soleus and semitendinosus) cardiac their structure properties compared with those of white C-protein. The Mr white, red, are 135,000, 145,000, 150,000, respectively, s20,w values 4.3, 3.8, 4.8 S, indicating that C-protein is more asymmetric than the other two. They elute quite differently hydroxylapatite columns. Two-dimensional CNBr peptide maps show extensive differences in primary structure, anti-white does not precipitate or Despite these structural differences, all three bind equally to myosin actin. All same effects on actomyosin ATPase 50 mM KCl; they inhibit actomyosins but slightly activate actomyosin. X-protein, a 140,000-dalton contaminant C-protein, was also investigated. It very similar elution columns, S20,w, amino acid composition, small indicate two proteins probably identical.