[Construction of microbial cell factories for synthesizing value-added chemicals with xylose]

Lignocellulose is the most abundant renewable resource on earth. Constructing microbial cell factories for synthesizing value-added chemicals with lignocellulose is the key to realize green biomanufacturing. Xylose is the second most fermentable sugar in lignocellulose after glucose. Building microbial cell factories that can efficiently metabolize xylose is of great significance to achieve full utilization of lignocellulose. However, the lower metabolism efficiency of xylose than that of glucose in most microorganisms limits the application of xylose. In recent years, the deepening understanding of microbial metabolic mechanisms and the continuous advancement of synthetic biology have greatly improved the efficiency of microbial metabolism of xylose and expanded the spectrum of xylose-derived products. This article introduces several xylose metabolic pathways that exist in the nature and the derived products, summarizes the strategies for constructing recombinant strains that can co-utilize xylose and glucose, and reviews the research progress in the application of lignocellulose hydrolysates in the synthesis of target products. Finally, this article discusses the current technical bottlenecks and prospects the future development directions in this field.