Partial purification and characterization of an extracellular protease fromXenorhabdus nematophilus, a symbiotic bacterium isolated from an entomopathogenic nematode,Steinernema glaseri

  • Young-Rae Chae
  • Keun-Garp Ryu


Entomopathogenic nematodes are used for insect control. Herein, an extracellular protease was partially purified from a culture supernatant ofXenorhabdus nematophilus, a symbiotic bacterium of an entomopathogenic nematode,Steinernema glaseri, using precipitation with 80% v/v isopropyl alcohol followed by gel permeation chromatography with a packed Sephacryl S-300 HR media. The partially purified protease exhibited maximal activity at pH 7 in the presence of 1 mM CaCl2. The protease was identified as a metallo-protease based on the inhibition of its activity by the metal chelating agent, EDTA.


entomopathogenic nematodes inhibitor protease symbiotic bacteria 


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Copyright information

© The Korean Society for Biotechnology and Bioengineering 2004

Authors and Affiliations

  1. 1.School of Chemical Engineering and BioengineeringUniversity of UlsanUlsanKorea

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