Enhanced ethanol production from lignocellulosic hydrolysates by inhibiting the hydrogen synthesis in Thermoanaerobacterium aotearoense SCUT27(Δ ldh )

2019 ◽  
Vol 94 (10) ◽  
pp. 3305-3314 ◽  
Author(s):  
Hongxin Fu ◽  
Xitong Yang ◽  
Chunyun Qu ◽  
Yang Li ◽  
Jufang Wang
Keyword(s):  
Ethanol Production ◽  
Lignocellulosic Hydrolysates ◽  
Hydrogen Synthesis

scholarly journals Engineering of sugar transporters for improvement of xylose utilization during high-temperature alcoholic fermentation in Ogataea polymorpha yeast

2020 ◽  
Author(s):  
Roksolana Vasylyshyn ◽  
Olena Kurylenko ◽  
Justyna Ruchala ◽  
Nadiya Shevchuk ◽  
Neringa Kuliesiene ◽  
...  
Keyword(s):  
Ethanol Production ◽  
Xylose Fermentation ◽  
Xylose Utilization ◽  
Wild Type ◽  
Xylose Consumption ◽  
Lignocellulosic Hydrolysates ◽  
Xylose Transport ◽  
Positive Effects ◽  
Arginine Residues ◽  
Ogataea Polymorpha

Abstract Background Xylose transport is one of the bottlenecks in the conversion of lignocellulosic biomass to ethanol. Xylose consumption by the wild-type strains of xylose-utilizing yeasts occurs once glucose is depleted resulting in a long fermentation process and overall slow and incomplete conversion of sugars liberated from lignocellulosic hydrolysates. Therefore, the engineering of endogenous transporters for the facilitation of glucose-xylose co-consumption is an important prerequisite for efficient ethanol production from lignocellulosic hydrolysates. Results In this study, several engineering approaches formerly used for the low-affinity glucose transporters in Saccharomyces cerevisiae , were successfully applied for earlier identified transporter Hxt1 in Ogataea polymorpha to improve xylose consumption (engineering involved asparagine substitution to alanine at position 358 and replacement of N-terminal lysine residues predicted to be the target of ubiquitination for arginine residues). Moreover, the modified versions of S. cerevisiae Hxt7 and Gal2 transporters also led to improved xylose fermentation when expressed in O. polymorpha . Conclusions The O. polymorpha strains with modified Hxt1 were characterized by simultaneous utilization of both glucose and xylose, in contrast to the wild-type and parental strain with elevated ethanol production from xylose. When the engineered Hxt1 transporter was introduced into constructed earlier advanced ethanol producer form xylose, the resulted strain showed further increase in ethanol accumulation during xylose fermentation. The overexpression of heterologous S. cerevisiae Gal2 had a less profound positive effects on sugars uptake rate, while overexpression of Hxt7 revealed the least impact on sugars consumption.

scholarly journals Engineering of sugar transporters for improvement of xylose utilization during high-temperature alcoholic fermentation in Ogataea polymorpha yeast

2020 ◽  
Author(s):  
Roksolana Vasylyshyn ◽  
Olena Kurylenko ◽  
Justyna Ruchala ◽  
Nadiya Shevchuk ◽  
Neringa Kuliesiene ◽  
...  
Keyword(s):  
Ethanol Production ◽  
Xylose Fermentation ◽  
Xylose Utilization ◽  
Wild Type ◽  
Xylose Consumption ◽  
Lignocellulosic Hydrolysates ◽  
Xylose Transport ◽  
Positive Effects ◽  
Arginine Residues ◽  
Ogataea Polymorpha

Abstract Background Xylose transport is one of the bottlenecks in the conversion of lignocellulosic biomass to ethanol. Xylose consumption by the wild-type strains of xylose-utilizing yeasts occurs once glucose is depleted resulting in a long fermentation process and overall slow and incomplete conversion of sugars liberated from lignocellulosic hydrolysates. Therefore, the engineering of endogenous transporters for the facilitation of glucose-xylose co-consumption is an important prerequisite for efficient ethanol production from lignocellulosic hydrolysates. Results In this study, several engineering approaches formerly used for the low-affinity glucose transporters in Saccharomyces cerevisiae , were successfully applied for earlier identified transporter Hxt1 in Ogataea polymorpha to improve xylose consumption (engineering involved asparagine substitution to alanine at position 358 and replacement of N-terminal lysine residues predicted to be the target of ubiquitination for arginine residues). Moreover, the modified versions of S. cerevisiae Hxt7 and Gal2 transporters also led to improved xylose fermentation when expressed in O. polymorpha . Conclusions The O. polymorpha strains with modified Hxt1 were characterized by simultaneous utilization of both glucose and xylose, in contrast to the wild-type and parental strain with elevated ethanol production from xylose. When the engineered Hxt1 transporter was introduced into constructed earlier advanced ethanol producer form xylose, the resulted strain showed further increase in ethanol accumulation during xylose fermentation. The overexpression of heterologous S. cerevisiae Gal2 had a less profound positive effects on sugars uptake rate, while overexpression of Hxt7 revealed the least impact on sugars consumption.

Ethanol production from selected lignocellulosic hydrolysates by genome shuffled strains of Scheffersomyces stipitis

2011 ◽  
Vol 102 (21) ◽  
pp. 9965-9969 ◽  
Author(s):  
Paramjit K. Bajwa ◽  
Chetsada Phaenark ◽  
Nicola Grant ◽  
Xiao Zhang ◽  
Michael Paice ◽  
...  
Keyword(s):  
Ethanol Production ◽  
Scheffersomyces Stipitis ◽  
Lignocellulosic Hydrolysates

Yeast strains for ethanol production from lignocellulosic hydrolysates during in situ detoxification

2009 ◽  
Vol 27 (5) ◽  
pp. 656-660 ◽  
Author(s):  
Shen Tian ◽  
Guixiong Zhou ◽  
Fei Yan ◽  
Yong Yu ◽  
Xiushan Yang
Keyword(s):  
Ethanol Production ◽  
Lignocellulosic Hydrolysates ◽  
Yeast Strains ◽  
In Situ Detoxification

scholarly journals Exploiting Type I-B CRISPR Genome Editing System in Thermoanaerobacterium Aotearoense SCUT27 And Engineering The Strain For High-Level Ethanol Production

2021 ◽  
Author(s):  
Kaiqun Dai ◽  
Hongxin Fu ◽  
Xiaolong Guo ◽  
Chunyun Qu ◽  
Jufang Wang
Keyword(s):  
Ethanol Production ◽  
Genome Editing ◽  
Gene Editing ◽  
Selection Marker ◽  
Type I ◽  
Lignocellulosic Hydrolysates ◽  
Editing Efficiency ◽  
Negative Selection Marker ◽  
Wide Range ◽  
High Level

Abstract Background: Thermophilic microbes for biofuels and chemicals have attracted great attention due to their tolerance of high temperature and wide range of substrate utilization. Thermoanaerobacterium aotearoense SCUT27 has the ability of glucose and xylose co-utilization in lignocellulosic biomass. Polygene manipulation was a bottleneck since it was hindered by available markers for selection. In this study, the endogenous Type I-B CRISPR/Cas system was developed for multiplex genome editing in SCUT27. Results: The protospacer-adjacent motif (PAM) was identified by in silico and orotidine-5’-phosphate decarboxylase (pyrF) and then lactate dehydrogenase (ldh) were chosen as the editing target to assess the toxicity of this immune system and gene editing efficiency. The mutants could be repeatedly obtained with an editing efficiency of 58.3-100%. Higher transformation efficiency was observed after optimization of some editing strategies. Furthermore, a new method was performed for screening mutants of plasmid curing (recycling of the editing plasmid) for multiplex genome editing based on the negative selection marker tdk, and then ldh and arginine repressor (argR) were knocked out successively. The mutant SCUT27/Δldh/ΔargR had the prominent advantages over SCUT27 for ethanol production with enhanced ability to metabolize xylose. When cultured under various lignocellulosic hydrolysates, the mutant showed a satisfactory performance with the ethanol titer and yield improved by 147.42–739.40% and 112.67–267.89%, respectively, compared with SCUT27, as well as the enhanced tolerance to inhibitors.Conclusion: The multi-gene editing by native CRISPR/Cas system is a promising strategy to engineer SCUT27 for higher ethanol production with lignocellulosic hydrolysates.

Sign in / Sign up

Export Citation Format

Share Document