Identification and characterization of cathepsin D in a highly purified sialidase from starfish A. pectinifera

Academic Article


  • A sialidase [EC] from the ovary of starfish Asterina pectinifera was isolated and highly purified by preparative PAGE. The SDS-PAGE separation of the purified enzyme revealed two natures of protein bands, upper (50 kDa) and a lower (47 kDa). To identify the protein, N-terminal amino acid sequence of the upper band was done. The sequence matched with the N-terminal amino acid sequence of human lysosomal mature cathepsin D and cathepsin D activity was also found in all the preparation steps. Protease inhibitor pepstatin A inhibited the proteolysis activity of cathepsin D against a synthetic substrate. The two enzymes sialidase and cathepsin D were separated from each other by using high-performance gel-filtration chromatography. The Western blot analysis and isoelectric focusing showed the co-purified cathepsin D is a 50 kDa protein with a PI value of 4.2. © 2007 The Japanese Biochemical Society.
  • Published In

    Digital Object Identifier (doi)

    Author List

  • Kannappan R; Satoh Y; Iriyama N; Ando M; Sawada MT; Takahashi N; Furuhata K; Uda Y
  • Start Page

  • 117
  • End Page

  • 122
  • Volume

  • 143
  • Issue

  • 1