dc.contributor.author	Ilmen, Marja
dc.contributor.author	Den Haan, Riaan
dc.contributor.author	Brevnova, Elena
dc.contributor.author	McBride, John
dc.contributor.author	Wiswall, Erin
dc.contributor.author	Froehlich, Allan
dc.contributor.author	Koivula, Anu
dc.contributor.author	Voutilainen, Sanni P.
dc.contributor.author	Siika-aho, Matti
dc.contributor.author	LaGrange, Daniel C.
dc.contributor.author	Thorngren, Naomi
dc.contributor.author	Ahlgren, Simon
dc.contributor.author	Mellon, Mark
dc.contributor.author	Deleault, Kristen
dc.contributor.author	Rajgarhia, Vineet
dc.contributor.author	Van Zyl, Willem H.
dc.contributor.author	Penttila, Merja
dc.date.accessioned	2011-10-11T16:08:44Z
dc.date.available	2011-10-11T16:08:44Z
dc.date.issued	2011-09
dc.date.updated	2011-10-07T05:10:32Z
dc.description	The original publication is available at http://www.biotechnologyforbiofuels.com/content/4/1/30
dc.description.abstract	BACKGROUND: The main technological impediment to widespread utilization of lignocellulose for the production of fuels and chemicals is the lack of low-cost technologies to overcome its recalcitrance. Organisms that hydrolyze lignocellulose and produce a valuable product such as ethanol at a high rate and titer could significantly reduce the costs of biomass conversion technologies, and will allow separate conversion steps to be combined in a consolidated bioprocess (CBP). Development of Saccharomyces cerevisiae for CBP requires the high level secretion of cellulases, particularly cellobiohydrolases. RESULTS: We expressed various cellobiohydrolases to identify enzymes that were efficiently secreted by S. cerevisiae. For enhanced cellulose hydrolysis, we engineered bimodular derivatives of a well secreted enzyme that naturally lacks the carbohydrate-binding module, and constructed strains expressing combinations of cbh1 and cbh2 genes. Though there was significant variability in the enzyme levels produced, up to approximately 0.3 g/L CBH1 and approximately 1 g/L CBH2 could be produced in high cell density fermentations. Furthermore, we could show activation of the unfolded protein response as a result of cellobiohydrolase production. Finally, we report fermentation of microcrystalline cellulose (Avicel™) to ethanol by CBH-producing S. cerevisiae strains with the addition of beta-glucosidase. CONCLUSIONS: Gene or protein specific features and compatibility with the host are important for efficient cellobiohydrolase secretion in yeast. The present work demonstrated that production of both CBH1 and CBH2 could be improved to levels where the barrier to CBH sufficiency in the hydrolysis of cellulose was overcome.	en_ZA
dc.description.version	Publishers' version	en_ZA
dc.format.extent	15 p. : ill.
dc.identifier.citation	Ilmén, Marja ... [et al.]. 2011.High level secretion of cellobiohydrolases by Saccharomyces cerevisiae. Biotechnology for biofuels. 4:30, 3-15, http://dx.doi.org/10.1186/1754-6834-4-30.	en_ZA
dc.identifier.issn	1754-6834
dc.identifier.other	http://dx.doi.org/10.1186/1754-6834-4-30
dc.identifier.uri	http://hdl.handle.net/10019.1/16612
dc.language.iso	en_ZA	en_ZA
dc.language.rfc3066	en
dc.publisher	BioMed Central	en_ZA
dc.rights.holder	Ilmen et al.; licensee BioMed Central Ltd.	en_ZA
dc.subject	Lignocellulose	en_ZA
dc.subject	Fuel	en_ZA
dc.subject	Biomass conversion technologies	en_ZA
dc.subject	Saccharomyces cerevisiae	en_ZA
dc.subject	Cellobiohydrolases	en_ZA
dc.title	High level secretion of cellobiohydrolases by Saccharomyces cerevisiae	en_ZA
dc.type	Article	en_ZA

High level secretion of cellobiohydrolases by Saccharomyces cerevisiae

Files

Original bundle

License bundle

Collections