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 Google Scholar
Google Scholar
Right arrow Articles by Nonklang, S.
Right arrow Articles by Akada, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Nonklang, S.
Right arrow Articles by Akada, R.
Agricola
Right arrow Articles by Nonklang, S.
Right arrow Articles by Akada, R.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, December 2008, p. 7514-7521, Vol. 74, No. 24
0099-2240/08/$08.00+0     doi:10.1128/AEM.01854-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

High-Temperature Ethanol Fermentation and Transformation with Linear DNA in the Thermotolerant Yeast Kluyveromyces marxianus DMKU3-1042{triangledown}

Sanom Nonklang,1 Babiker M. A. Abdel-Banat,1 Kamonchai Cha-aim,1 Nareerat Moonjai,2 Hisashi Hoshida,1 Savitree Limtong,3 Mamoru Yamada,1 and Rinji Akada1*

Department of Applied Molecular Bioscience, Yamaguchi University Graduate School of Medicine, Tokiwadai, Ube 755-8611, Japan,1 Department of Biological Science, Faculty of Science, Ubon Ratchathani University, Ubon Ratchathani 34190,2 Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand3

Received 11 August 2008/ Accepted 13 October 2008

We demonstrate herein the ability of Kluyveromyces marxianus to be an efficient ethanol producer and host for expressing heterologous proteins as an alternative to Saccharomyces cerevisiae. Growth and ethanol production by strains of K. marxianus and S. cerevisiae were compared under the same conditions. K. marxianus DMKU3-1042 was found to be the most suitable strain for high-temperature growth and ethanol production at 45°C. This strain, but not S. cerevisiae, utilized cellobiose, xylose, xylitol, arabinose, glycerol, and lactose. To develop a K. marxianus DMKU3-1042 derivative strain suitable for genetic engineering, a uracil auxotroph was isolated and transformed with a linear DNA of the S. cerevisiae ScURA3 gene. Surprisingly, Ura+ transformants were easily obtained. By Southern blot hybridization, the linear ScURA3 DNA was found to have inserted randomly into the K. marxianus genome. Sequencing of one Lys transformant confirmed the disruption of the KmLYS1 gene by the ScURA3 insertion. A PCR-amplified linear DNA lacking K. marxianus sequences but containing an Aspergillus {alpha}-amylase gene under the control of the ScTDH3 promoter together with an ScURA3 marker was subsequently used to transform K. marxianus DMKU3-1042 in order to obtain transformants expressing Aspergillus {alpha}-amylase. Our results demonstrate that K. marxianus DMKU3-1042 can be an alternative cost-effective bioethanol producer and a host for transformation with linear DNA by use of S. cerevisiae-based molecular genetic tools.


* Corresponding author. Mailing address: Department of Applied Molecular Bioscience, Yamaguchi University Graduate School of Medicine, Tokiwadai, Ube 755-8611, Japan. Phone: 81 836 85 9292. Fax: 81 836 85 9201. E-mail: rinji{at}yamaguchi-u.ac.jp

{triangledown} Published ahead of print on 17 October 2008.


Applied and Environmental Microbiology, December 2008, p. 7514-7521, Vol. 74, No. 24
0099-2240/08/$08.00+0     doi:10.1128/AEM.01854-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.