TY  - JOUR
A1  - Tamayo Rojas, Sebastián Alfredo
A1  - Schadeweg, Virginia
A1  - Kirchner, Ferdinand
A1  - Boles, Eckhard
A1  - Oreb, Igor-Mislav
T1  - Identification of a glucose-insensitive variant of Gal2 from Saccharomyces cerevisiae exhibiting a high pentose transport capacity
T2  - Scientific reports
N2  - As abundant carbohydrates in renewable feedstocks, such as pectin-rich and lignocellulosic hydrolysates, the pentoses arabinose and xylose are regarded as important substrates for production of biofuels and chemicals by engineered microbial hosts. Their efficient transport across the cellular membrane is a prerequisite for economically viable fermentation processes. Thus, there is a need for transporter variants exhibiting a high transport rate of pentoses, especially in the presence of glucose, another major constituent of biomass-based feedstocks. Here, we describe a variant of the galactose permease Gal2 from Saccharomyces cerevisiae (Gal2N376Y/M435I), which is fully insensitive to competitive inhibition by glucose, but, at the same time, exhibits an improved transport capacity for xylose compared to the wildtype protein. Due to this unique property, it significantly reduces the fermentation time of a diploid industrial yeast strain engineered for efficient xylose consumption in mixed glucose/xylose media. When the N376Y/M435I mutations are introduced into a Gal2 variant resistant to glucose-induced degradation, the time necessary for the complete consumption of xylose is reduced by approximately 40%. Moreover, Gal2N376Y/M435I confers improved growth of engineered yeast on arabinose. Therefore, it is a valuable addition to the toolbox necessary for valorization of complex carbohydrate mixtures.
KW  - Carbohydrates
KW  - Metabolic engineering
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/69538
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-695384
SN  - 2045-2322
N1  - Open Access funding enabled and organized by Projekt DEAL.
VL  - 11
IS  - art. 24404
SP  - 1
EP  - 10
PB  - Macmillan Publishers Limited, part of Springer Nature
CY  - [London]
ER  -