Comparison of the amino acid sequence of pig heart myoglobin with other ungulate myoglobins.

The primary structure of pig heart myoglobin has been established by study of the tryptic peptides of whole globin and by analysis of the fragments obtained by CNBr cleavage. Thermolysin and chymotrypsin digestion were used to determine the sequence of the M fragment (56-131). Automatic Edman degradation of whole globin and of the M fragment completed the sequence of pig myoglobin. Comparison with other ungulates shows that pig myoglobin is far from other artiodactyls previously studied (ox and sheep) and close to the eutherian ancestral chain.