[Comparative study of preparations of hirudin and "pseudohirudin"]

In contrast to hirudin, "pseudohirudin", which is practically devoid of the antithrombin activity, is represented as associates of di- and trimers. The molecular weight of the "pseudohirudin" monomer is by 2000 less than that for hirudin. This corresponds to the 20 amino acid residues difference calculated from the total number of the amino acid residues. Changes in the amino acid composition consist in a higher content of dicarboxylic amino acids, isoleucine, lysine, tyrosine and cystein in the hirudin preparations.