Isolation of Two Bovine Amelogenin Peptides and their Amino Acid Sequences

¹ Department of Biochemistry, School of Dentistry, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113, Japan

Dr. S. Sasaki, Department of Biochemistry, School of Dentistry, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-Ku, Tokyo 113, Japan.

Two peptide fractions of bovine amelogenin having a highly aggregative property to form polymers were purified by chromatography, SDS-polyacrylamide gel electrophoresis, and HPLC. Amino acid sequences of purified peptides were determined by automated Edman degradation. One peptide was found to be composed of 63 amino acid residues having a molecular weight of 7105, and the other of 86 residues having that of 9683. The sequence of the smaller peptide was identical to the C-terminal 63 residues of the amelogenin molecule of 170 residues previously reported, but the larger contained eight residues which are absent in the amelogenin sequence. There is a possibility that the latter peptide might be synthesized independently from mRNA spliced at different positions.