AMINO ACID ANALYSIS AND PEPTIDE MAPPING OF BOVINE CAROTID ACTIN

Actin from bovine carotid is found to be essentially similar to actins extracted from other muscular tissues, as demonstrated by amino acid analysis and peptide mapping. So far no difference in molecular structure has been detected which could account for the unusual incomplete depolymerization of this actin. 3-Methylhistidine is present at a ratio of 1 per 8 histidines, similar to that found in rabbit actin. This ratio tends to indicate that the molecular weight of actin monomer from smooth and striated muscle is near 48 000, instead of the previously accepted value of 60 000. © 1969.