TY - JOUR
T1 - The introduction of the fungal D-galacturonate pathway enables the consumption of D-galacturonic acid by Saccharomyces cerevisiae
AU - Biz, Alessandra
AU - Sugai-Guérios, Maura Harumi
AU - Kuivanen, Joosu
AU - Maaheimo, Hannu
AU - Krieger, Nadja
AU - Mitchell, David Alexander
AU - Richard, Peter
N1 - SDA: SHP: Bioeconomy
Project code: 100686
PY - 2016
Y1 - 2016
N2 - Background: Pectin-rich wastes, such as citrus pulp and
sugar beet pulp, are produced in considerable amounts by
the juice and sugar industry and could be used as raw
materials for biorefineries. One possible process in such
biorefineries is the hydrolysis of these wastes and the
subsequent production of ethanol. However, the
ethanol-producing organism of choice, Saccharomyces
cerevisiae, is not able to catabolize d-galacturonic
acid, which represents a considerable amount of the
sugars in the hydrolysate, namely, 18 % (w/w) from citrus
pulp and 16 % (w/w) sugar beet pulp.
Results: In the current work, we describe the
construction of a strain of S. cerevisiae in which the
five genes of the fungal reductive pathway for
d-galacturonic acid catabolism were integrated into the
yeast chromosomes: gaaA, gaaC and gaaD from Aspergillus
niger and lgd1 from Trichoderma reesei, and the recently
described d-galacturonic acid transporter protein, gat1,
from Neurospora crassa. This strain metabolized
d-galacturonic acid in a medium containing d-fructose as
co-substrate.
Conclusion: This work is the first demonstration of the
expression of a functional heterologous pathway for
d-galacturonic acid catabolism in Saccharomyces
cerevisiae. It is a preliminary step for engineering a
yeast strain for the fermentation of pectin-rich
substrates to ethanol.
AB - Background: Pectin-rich wastes, such as citrus pulp and
sugar beet pulp, are produced in considerable amounts by
the juice and sugar industry and could be used as raw
materials for biorefineries. One possible process in such
biorefineries is the hydrolysis of these wastes and the
subsequent production of ethanol. However, the
ethanol-producing organism of choice, Saccharomyces
cerevisiae, is not able to catabolize d-galacturonic
acid, which represents a considerable amount of the
sugars in the hydrolysate, namely, 18 % (w/w) from citrus
pulp and 16 % (w/w) sugar beet pulp.
Results: In the current work, we describe the
construction of a strain of S. cerevisiae in which the
five genes of the fungal reductive pathway for
d-galacturonic acid catabolism were integrated into the
yeast chromosomes: gaaA, gaaC and gaaD from Aspergillus
niger and lgd1 from Trichoderma reesei, and the recently
described d-galacturonic acid transporter protein, gat1,
from Neurospora crassa. This strain metabolized
d-galacturonic acid in a medium containing d-fructose as
co-substrate.
Conclusion: This work is the first demonstration of the
expression of a functional heterologous pathway for
d-galacturonic acid catabolism in Saccharomyces
cerevisiae. It is a preliminary step for engineering a
yeast strain for the fermentation of pectin-rich
substrates to ethanol.
KW - ethanol
KW - d-galacturonic acid
KW - Saccharomyces cerevisiae
KW - citrus pulp
KW - metabolic engineering
U2 - 10.1186/s12934-016-0544-1
DO - 10.1186/s12934-016-0544-1
M3 - Article
VL - 15
JO - Microbial Cell Factories
JF - Microbial Cell Factories
SN - 1475-2859
IS - 144
ER -