Direct isolation of functional genes encoding cellulases from the microbial consortia in a thermophilic, anaerobic digester maintained on lignocellulose

  title={Direct isolation of functional genes encoding cellulases from the microbial consortia in a thermophilic, anaerobic digester maintained on lignocellulose},
  author={Frank Healy and Ramesh M. Ray and Henry C. Aldrich and Ann C. Wilkie and Lonnie O'Neal Ingram and Keelnatham T Shanmugam},
  journal={Applied Microbiology and Biotechnology},
Gene libraries (“zoolibraries”) were constructed in Escherichia coli using DNA isolated from the mixed liquor of thermophilic, anaerobic digesters, which were in continuous operation with lignocellulosic feedstocks for over 10 years. Clones expressing cellulase and xylosidase were readily recovered from these libraries. Four clones that hydrolyzed carboxymethylcellulose and methylumbelliferyl-β-d-cellobiopyranoside were characterized. All four cellulases exhibited temperature optima (60–65° C… 

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