TY - JOUR
T1 - Xylose metabolism in bacteria—opportunities and challenges towards efficient lignocellulosic biomass‐based biorefineries
AU - Domingues, Rafael
AU - Bondar, Maryna
AU - Palolo, Inês
AU - Queirós, Odília
AU - Dias de Almeida, Catarina
AU - Cesário, M. Teresa
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/9/1
Y1 - 2021/9/1
N2 - In a sustainable society based on circular economy, the use of waste lignocellulosic bio-mass (LB) as feedstock for biorefineries is a promising solution, since LB is the world’s most abundant renewable and non‐edible raw material. LB is available as a by‐product from agricultural and forestry processes, and its main components are cellulose, hemicellulose, and lignin. Following suitable physical, enzymatic, and chemical steps, the different fractions can be processed and/or converted to value‐added products such as fuels and biochemicals used in several branches of industry through the implementation of the biorefinery concept. Upon hydrolysis, the carbohydrate‐rich fraction may comprise several simple sugars (e.g., glucose, xylose, arabinose, and mannose) that can then be fed to fermentation units. Unlike pentoses, glucose and other hexoses are readily processed by microorganisms. Some wild‐type and genetically modified bacteria can metabolize xylose through three different main pathways of metabolism: xylose isomerase pathway, oxidoreductase pathway, and non‐phosphorylative pathway (including Weimberg and Dahms pathways). Two of the commercially interesting intermediates of these pathways are xylitol and xylonic acid, which can accumulate in the medium either through manipulation of the culture conditions or through genetic modification of the bacteria. This paper provides a state‐of‐the art perspective regarding the current knowledge on xylose transport and metabolism in bacteria as well as envisaged strategies to further increase xylose conversion into valuable products.
AB - In a sustainable society based on circular economy, the use of waste lignocellulosic bio-mass (LB) as feedstock for biorefineries is a promising solution, since LB is the world’s most abundant renewable and non‐edible raw material. LB is available as a by‐product from agricultural and forestry processes, and its main components are cellulose, hemicellulose, and lignin. Following suitable physical, enzymatic, and chemical steps, the different fractions can be processed and/or converted to value‐added products such as fuels and biochemicals used in several branches of industry through the implementation of the biorefinery concept. Upon hydrolysis, the carbohydrate‐rich fraction may comprise several simple sugars (e.g., glucose, xylose, arabinose, and mannose) that can then be fed to fermentation units. Unlike pentoses, glucose and other hexoses are readily processed by microorganisms. Some wild‐type and genetically modified bacteria can metabolize xylose through three different main pathways of metabolism: xylose isomerase pathway, oxidoreductase pathway, and non‐phosphorylative pathway (including Weimberg and Dahms pathways). Two of the commercially interesting intermediates of these pathways are xylitol and xylonic acid, which can accumulate in the medium either through manipulation of the culture conditions or through genetic modification of the bacteria. This paper provides a state‐of‐the art perspective regarding the current knowledge on xylose transport and metabolism in bacteria as well as envisaged strategies to further increase xylose conversion into valuable products.
KW - Biorefinery
KW - Circular economy
KW - D‐xylose
KW - Sustainable processes
KW - Xylose metabolism in bacteria
UR - http://www.scopus.com/inward/record.url?scp=85114226759&partnerID=8YFLogxK
U2 - 10.3390/app11178112
DO - 10.3390/app11178112
M3 - Review article
AN - SCOPUS:85114226759
SN - 2076-3417
VL - 11
JO - Applied Sciences (Switzerland)
JF - Applied Sciences (Switzerland)
IS - 17
M1 - 8112
ER -