This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Cohen, R.
Right arrow Articles by Hammel, K. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Cohen, R.
Right arrow Articles by Hammel, K. E.
Agricola
Right arrow Articles by Cohen, R.
Right arrow Articles by Hammel, K. E.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, May 2005, p. 2412-2417, Vol. 71, No. 5
0099-2240/05/$08.00+0     doi:10.1128/AEM.71.5.2412-2417.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Processive Endoglucanase Active in Crystalline Cellulose Hydrolysis by the Brown Rot Basidiomycete Gloeophyllum trabeum

Roni Cohen,1,{dagger} Melissa R. Suzuki,2 and Kenneth E. Hammel1,2*

Department of Bacteriology, University of Wisconsin, Madison, Wisconsin 53706,1 Institute for Microbial and Biochemical Technology, USDA Forest Products Laboratory, Madison, Wisconsin 537262

Received 30 September 2004/ Accepted 9 December 2004

Brown rot basidiomycetes have long been thought to lack the processive cellulases that release soluble sugars from crystalline cellulose. On the other hand, these fungi remove all of the cellulose, both crystalline and amorphous, from wood when they degrade it. To resolve this discrepancy, we grew Gloeophyllum trabeum on microcrystalline cellulose (Avicel) and purified the major glycosylhydrolases it produced. The most abundant extracellular enzymes in these cultures were a 42-kDa endoglucanase (Cel5A), a 39-kDa xylanase (Xyn10A), and a 28-kDa endoglucanase (Cel12A). Cel5A had significant Avicelase activity—4.5 nmol glucose equivalents released/min/mg protein. It is a processive endoglucanase, because it hydrolyzed Avicel to cellobiose as the major product while introducing only a small proportion of reducing sugars into the remaining, insoluble substrate. Therefore, since G. trabeum is already known to produce a ß-glucosidase, it is now clear that this brown rot fungus produces enzymes capable of yielding assimilable glucose from crystalline cellulose.

* Corresponding author. Mailing address: Institute for Microbial and Biochemical Technology, USDA Forest Products Laboratory, One Gifford Pinchot Drive, Madison, WI 53726. Phone: (608) 231-9528. Fax: (608) 231-9262. E-mail: kehammel{at}wisc.edu.

{dagger} Present address: Sigma-Aldrich Israel, Ltd., 97770 Jerusalem, Israel.

Applied and Environmental Microbiology, May 2005, p. 2412-2417, Vol. 71, No. 5
0099-2240/05/$08.00+0     doi:10.1128/AEM.71.5.2412-2417.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Watson, B. J., Zhang, H., Longmire, A. G., Moon, Y. H., Hutcheson, S. W. (2009). Processive Endoglucanases Mediate Degradation of Cellulose by Saccharophagus degradans. J. Bacteriol. 191: 5697-5705 [Abstract] [Full Text]  
  • Shimokawa, T., Shibuya, H., Nojiri, M., Yoshida, S., Ishihara, M. (2008). Purification, Molecular Cloning, and Enzymatic Properties of a Family 12 Endoglucanase (EG-II) from Fomitopsis palustris: Role of EG-II in Larch Holocellulose Hydrolysis. Appl. Environ. Microbiol. 74: 5857-5861 [Abstract] [Full Text]  
  • Valaskova, V., Baldrian, P. (2006). Degradation of cellulose and hemicelluloses by the brown rot fungus Piptoporus betulinus - production of extracellular enzymes and characterization of the major cellulases. Microbiology 152: 3613-3622 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»