Bovine alpha 2-antiplasmin. N-terminal and reactive site sequence.

Bovine alpha 2-antiplasmin (alpha 2AP) has been purified and partially characterized. The amino acid composition is very similar to that of human alpha 2AP, and the N-terminal (23 residues determined) and reactive site loop sequences (42 residues determined) are highly homologous to those of the human protein. Compared with human alpha 2AP, bovine alpha 2AP has an 18-residue N-terminal extension, homologous with part of the pre-sequence of human alpha 2AP. A re-investigation of the N-terminal sequence of freshly prepared human alpha 2AP reveals a new form extended by 12 residues.