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 Koukiekolo, R.
Right arrow Articles by Doi, R. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Koukiekolo, R.
Right arrow Articles by Doi, R. H.
Agricola
Right arrow Articles by Koukiekolo, R.
Right arrow Articles by Doi, R. H.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, July 2005, p. 3504-3511, Vol. 71, No. 7
0099-2240/05/$08.00+0     doi:10.1128/AEM.71.7.3504-3511.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Degradation of Corn Fiber by Clostridium cellulovorans Cellulases and Hemicellulases and Contribution of Scaffolding Protein CbpA

Roger Koukiekolo,1 Hee-Yeon Cho,1 Akihiko Kosugi,1,{dagger} Masayuki Inui,2 Hideaki Yukawa,2 and Roy H. Doi1*

Section of Molecular and Cellular Biology, University of California, Davis, California 95616,1 Research Institute of Innovative Technology for the Earth, Kyoto 619-0292, Japan2

Received 24 August 2004/ Accepted 17 January 2005

Clostridium cellulovorans, an anaerobic bacterium, degrades native substrates efficiently by producing an extracellular enzyme complex called the cellulosome. All cellulosomal enzyme subunits contain dockerin domains that can bind to hydrophobic domains termed cohesins which are repeated nine times in CbpA, the nonenzymatic scaffolding protein of C. cellulovorans cellulosomes. In this study, the synergistic interactions of cellulases (endoglucanase E, EngE; endoglucanase L, EngL) and hemicellulases (arabinofuranosidase A, ArfA; xylanase A, XynA) were determined on the degradation of corn fiber, a natural substrate containing mainly xylan, arabinan, and cellulose. The degradation by XynA and ArfA of cellulose/arabinoxylan was greater than that of corn fiber and resulted in 2.6-fold and 1.4-fold increases in synergy, respectively. Synergistic effects were observed in increments in both simultaneous and sequential reactions with ArfA and XynA. These synergistic enzymes appear to represent potential rate-limiting enzymes for efficient hemicellulose degradation. When mini-cellulosomes were constructed from the cellulosomal enzymes (XynA and EngL) and mini-CbpA with cohesins 1 and 2 (mini-CbpA1&2) and mini-CbpA with cohesins 5 and 6 (mini-CbpA5&6), higher activity was observed than that for the corresponding enzymes alone. Based on the degradation of different types of celluloses and hemicelluloses, the interaction between cellulosomal enzymes (XynA and EngL) and mini-CbpA displayed a diversity that suggests that dockerin-cohesin interaction from C. cellulovorans may be more selective than random.

* Corresponding author. Mailing address: Section of Molecular & Cellular Biology, University of California, Davis, CA 95616. Phone: (530) 752-3191. Fax: (530) 752-3085. E-mail: rhdoi{at}ucdavis.edu.

{dagger} Present address: Japan International Research Center for Agricultural Sciences (JIRCAS), Tsukuba, Ibaraki 305-8686, Japan.

Applied and Environmental Microbiology, July 2005, p. 3504-3511, Vol. 71, No. 7
0099-2240/05/$08.00+0     doi:10.1128/AEM.71.7.3504-3511.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Matsuoka, S., Yukawa, H., Inui, M., Doi, R. H. (2007). Synergistic Interaction of Clostridium cellulovorans Cellulosomal Cellulases and HbpA. J. Bacteriol. 189: 7190-7194 [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»