Construction of cellobiose-growing and fermenting Saccharomyces cerevisiae strains

Date
2004-12
Authors
Van Rooyen, Ronel
Hahn-Hagerdal, Barbel
La Grange, Daniel C.
Van Zyl, Willem H.
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier
Abstract
β-Glucosidase genes of fungal origins were isolated and heterologously expressed in Saccharomyces cerevisiae to enable growth on the disaccharide, cellobiose. To promote secretion of the β-glucosidases, the genes were fused to the secretion signal of the Trichoderma reesei xyn2 gene and constitutively expressed from a multi-copy yeast expression vector under transcriptional control of the S. cerevisiae PGK1 promoter and terminator. The resulting recombinant enzymes were characterized with respect to pH and temperature optimum, as well as kinetic properties. The two most promising enzymes, BGL1 from Saccharomycopsis fibuligera and BglA from Aspergillus kawachii, were anchored to the yeast cell surface by fusing the mature proteins to the α-agglutinin (AGα1) or cell wall protein 2 (Cwp2) peptides. The maximum specific growth rates (μmax) of the recombinant S. cerevisiae strains were determined in batch cultivation. S. cerevisiae secreting the recombinant S. fibuligera BGL1 enzyme sustained growth aerobically and anaerobically, in minimal medium containing 5 g L−1 cellobiose at 0.23 h−1 (compared to 0.29 h−1 on glucose) and 0.18 h−1 (compared to 0.25 h−1 on glucose), respectively. Substrate consumption and product formation were determined to evaluate product yields in glucose and cellobiose.
Description
The original publication is available at www.elsevier.com.
Includes bibliography.
Keywords
Saccharomyces cerevisiae, Heterologous, Proteins, Production, Glucosidase, Cellobiose, Fermentation, Yeast, Saccharomycopsis, Fibuligera
Citation
Van Rooyen, Ronel, Hahn-Hagerdal, Barbel, La Grange, Daniel C., Van Zyl, Willem H. 2005. Construction of cellobiose-growing and fermenting Saccharomyces cerevisiae strains. Journal of Biotechnology, 120:284-295, doi:10.1016/j.jbiotec.2005.06.013, http://www.sciencedirect.com.ez.sun.ac.za/science?_ob=MImg&_imagekey=B6T3C-4GT7G4B-2-5&_cdi=4943&_user=613892&_pii=S0168165605003287&_origin=search&_coverDate=11%2F21%2F2005&_sk=998799996&view=c&wchp=dGLzVtb-zSkWA&md5=11828ed45ab4e0d3fd2466801b8359f6&ie=/sdarticle.pdf