Xylose Metabolism in Bacteria—Opportunities and Challenges towards Efficient Lignocellulosic Biomass-Based Biorefineries

Applied Sciences

Catarina Dias de Almeida¹  Odília Queirós²  Rafael Domingues³  Maryna Bondar³  Inês Palolo³  M. Teresa Cesário³ 

[1] Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz, Quinta da Granja, 2829-511 Monte da Caparica, Portugal;IINFACTS—Institute of Research and Advanced Training in Health Sciences and Technologies, Department of Sciences, University Institute of Health Sciences (IUCS), CESPU, Rua Central de Gandra, 1317, 4585-116 Gandra, Portugal;Institute for Bioengineering and Biosciences (iBB), Bioengineering Department, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal;

关键词: D-xylose;    biorefinery;    circular economy;    sustainable processes;    xylose metabolism in bacteria;   

DOI  :  10.3390/app11178112

来源: DOAJ

【 摘 要 】

In a sustainable society based on circular economy, the use of waste lignocellulosic biomass (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.

【 授权许可】

Unknown