Current Genetics

, 48:195 | Cite as

Characterization of the Lentinula edodes exg2 gene encoding a lentinan-degrading exo-β-1,3-glucanase

  • Yuichi SakamotoEmail author
  • Ken-ichiro Minato
  • Masaru Nagai
  • Masashi Mizuno
  • Toshitsugu Sato
Research Article


Lentinan, an antitumor substance purified from Lentinula edodes, is degraded during post-harvest preservation as a result of increased glucanase activity. We isolated an exo-β-1,3-glucanase encoding gene, exg2, from L. edodes which is a homologue of an exo-glucanase-encoding gene conserved in ascomycetous fungi. The exg2 gene was cloned as an approximately 2.4-kbp cDNA, and as a genomic sequence of 3.9-kbp. The product of the exg2 gene is predicted to contain 759 amino acids with a molecular weight of 79 kDa and a pI value of 4.6. The putative N-terminus of EXG2 is identical to the N-terminal sequences of lentinan-degrading enzymes, GNase I and II, and a custom-made anti-EXG2 peptide anti-serum cross-reacted with purified GNase I and II. Transcription and translation of exg2 was low in the gills of mature fruiting bodies, but increased after harvesting. We conclude that the exg2 gene is a lentinan-degrading enzyme-encoding-gene in L. edodes.


Cell wall lysis Exo-glucanase Fruiting body differentiation Lentinan degradation Lentinula edodes 


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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Yuichi Sakamoto
    • 1
    Email author
  • Ken-ichiro Minato
    • 2
  • Masaru Nagai
    • 1
    • 4
  • Masashi Mizuno
    • 3
  • Toshitsugu Sato
    • 1
  1. 1.Iwate Biotechnology Research CenterKitakami-shiJapan
  2. 2.Miyagi Agriculture CollegeTaihaku, SendaiJapan
  3. 3.Faculty of Agriculture, Kobe UniversityNada-kuJapan
  4. 4.Institute for Environmental ScienceObuchi, Rokkasho-mura, Kamikita-gunJapan

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