Amino acid sequence of starfish oocyte depactin.

The amino acid sequence of starfish oocyte depactin was determined by aligning lysyl endopeptidase, Staphylococcus aureus V8 protease, and cyanongen bromide peptides. Starfish oocyte depactin is composed of 150 amino acid residues and the N terminus is free proline. The molecular weight is calculated to be 17,590, in good agreement with the value estimated by sodium dodecyl-polyacrylamide gel electrophoresis. Prediction of the secondary structure shows that depactin contains 64% alpha-helix. Comparison of depactin sequence with those of other proteins shows no significant similarity.