Li Jinyang, Jiang Fangting, Pi Changyu, Bao Tongtong, Gao Le, Wu Xin
National Center of Technology Innovation for Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China.
National Center of Technology Innovation for Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China.
Int J Biol Macromol. 2024 Dec;282(Pt 5):137134. doi: 10.1016/j.ijbiomac.2024.137134. Epub 2024 Oct 30.
Lignin utilization is one of the key challenges in the valorziation of lignocellulose. Filamentous fungi are promising candidates for lignin degradation and mineralization. However, novel lignin-degrading species are underexplored and the mechanism of lignin degradation is not fully understood. Here we isolated and characterized a novel species, Myrothecium wuxin, capable of utilizing lignosulfonate as the sole carbon source. To understand the mechanism of lignin degradation, genomic, transcriptomic and metabolic analyses were performed. The genome was sequenced, and assembled to a size of 48.55 Mb, with a contig N50 size of 5.67Mb. A total of 14,221 protein-coding genes were predicted, including a high number of potential ligninolytic enzymes. Transcriptomic analysis revealed a pronounced effect of lignosulfonate on gene expression profiles. More than twenty intermediate aromatic metabolites were identified during lignosulfonate utilization. Through genomic annotation, the genes potentially involved in lignin degradation were identified, and more than nine metabolic pathways of lignin-derived aromatic intermediates were predicted, including the homogentisate pathway, benzoic acid pathway, as well as the tree-branched β-ketoadipate pathway. The genomic information will provide a valuable resource for lignin degradation, while the elucidated catabolic pathways and associated enzymes provide exciting biotechnological opportunities for lignin valorization and production of valuable chemicals.
木质素利用是木质纤维素增值过程中的关键挑战之一。丝状真菌是木质素降解和矿化的有潜力的候选者。然而，新型木质素降解物种尚未得到充分探索，木质素降解机制也尚未完全了解。在此，我们分离并鉴定了一个能够利用木质素磺酸盐作为唯一碳源的新物种——无锡漆斑菌。为了了解木质素降解机制，我们进行了基因组、转录组和代谢分析。对该基因组进行了测序，并组装成大小为48.55 Mb的序列，重叠群N50大小为5.67 Mb。共预测了14221个蛋白质编码基因，其中包括大量潜在的木质素分解酶。转录组分析揭示了木质素磺酸盐对基因表达谱有显著影响。在利用木质素磺酸盐的过程中鉴定出了二十多种中间芳香族代谢产物。通过基因组注释，确定了可能参与木质素降解的基因，并预测了九条以上木质素衍生芳香族中间体的代谢途径，包括尿黑酸途径、苯甲酸途径以及分支的β-酮己二酸途径。该基因组信息将为木质素降解提供宝贵资源，而阐明的分解代谢途径和相关酶为木质素增值和生产有价值的化学品提供了令人兴奋的生物技术机会。
