Purification and characterization of cathepsin B from the gut of the sea cucumber (Stichopus japonicas)

Li Ming Sun, Bei Wei Zhu, Hai tao Wu, Lei Yu, Da Yong Zhou, Xiuping Dong, Jing Feng Yang, Dong Mei Li, Wen Xiu Ye, Yoshiyuki Murata

Research output: Contribution to journalArticlepeer-review

34 Citations (Scopus)


Cathepsin B from the gut of sea cucumber (Stichopus japonicas) was purified 81-fold with a 3% recovery by ammonium sulfate fractionation and a series chromatography on DEAE Sepharose CL-6B, Sephadex G-75, and TSK-Gel 3000 SWxl. The purified protein appeared as a single band on Native-PAGE but showed 2 bands of 23 and 26 kDa on SDS-PAGE. The optimum activity was found at pH 5.5 and 45°C. The enzyme was stable at pH 4. 5-6. 0 and the thermal stability was up to 50°C. The enzyme was strongly inhibited by E-64, iodoacetic acid, and antipain, demonstrating it is a cysteine protease containing sulfhydryl groups. Cu 2+, Ni 2+, and Zn 2+ could strongly inhibit the enzyme activity. The amino acid sequences of the purified enzyme were acquired by mass spectrometer, which did not show any homology with previously described cathepsins, suggesting it may be a novel member.

Original languageEnglish
Pages (from-to)919-925
Number of pages7
JournalFood Science and Biotechnology
Issue number4
Publication statusPublished - Aug 2011


  • cathepsin B
  • characterization
  • purification
  • sea cucumber (Stichopus japonicus)

ASJC Scopus subject areas

  • Biotechnology
  • Food Science
  • Applied Microbiology and Biotechnology


Dive into the research topics of 'Purification and characterization of cathepsin B from the gut of the sea cucumber (Stichopus japonicas)'. Together they form a unique fingerprint.

Cite this