The primary structure of the alpha subunit of protocatechuate 3,4-dioxygenase. II. Isolation and sequence of overlap peptides and complete sequence.

The complete primary structure of the alpha subunit of protocatechuate 3,4-dioxygenase has been determined by automated Edman degradation and carboxypeptidase digestionof the intact alpha chain and of peptides derived from trypsin (N.A. Kohlmiller and J.B. Howard (1979) J. Biol. Chem. 254, 7302-7308) and Staphylococcus aureus protease digestion, and from hydroxylamine and dilute acid cleavage. The alpha chain was found to consist of 200 residues in the following sequence from the NH2-terminal end: (formula: see text).