Hsin Kuan-Ting, Lee HueyTyng, Huang Yu-Chun, Lin Guan-Jun, Lin Pei-Yu, Lin Ying-Chung Jimmy, Chen Pao-Yang
Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan.
Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung City, Taiwan.
Front Microbiol. 2025 Apr 25;16:1583746. doi: 10.3389/fmicb.2025.1583746. eCollection 2025.
Lignocellulose biomass is one of the most abundant resources for sustainable biofuels. However, scaling up the biomass-to-biofuels conversion process for widespread usage is still pending. One of the main bottlenecks is the high cost of enzymes used in key process of biomass degradation. Current research efforts are therefore targeted at creative solutions to improve the feasibility of lignocellulosic-degrading enzymes. One way is to engineer multi-enzyme complexes that mimic the bacterial cellulosomal system, known to increase degradation efficiency up to 50-fold when compared to freely-secreted enzymes. However, these designer cellulosomes are instable and less efficient than wild type cellulosomes. In this review, we aim to extensively analyze the current knowledge on the lignocellulosic-degrading enzymes through three aspects. We start by reviewing and comparing sets of enzymes in bacterial and fungal lignocellulose degradation. Next, we focus on the characteristics of cellulosomes in both systems and their feasibility to be engineered. Finally, we highlight three key strategies to enhance enzymatic lignocellulose degradation efficiency: discovering novel lignocellulolytic species and enzymes, bioengineering enzymes for improved thermostability, and structurally optimizing designer cellulosomes. We anticipate these insights to act as resources for the biomass community looking to elevate the usage of lignocellulose as biofuel.
木质纤维素生物质是可持续生物燃料最丰富的资源之一。然而,扩大生物质到生物燃料的转化过程以实现广泛应用仍有待解决。主要瓶颈之一是生物质降解关键过程中使用的酶成本高昂。因此,当前的研究工作旨在寻找创新解决方案,以提高木质纤维素降解酶的可行性。一种方法是构建模仿细菌纤维小体系统的多酶复合物,已知与自由分泌的酶相比,其降解效率可提高50倍。然而,这些设计的纤维小体不稳定,且比野生型纤维小体效率更低。在本综述中,我们旨在从三个方面广泛分析当前关于木质纤维素降解酶的知识。我们首先回顾和比较细菌和真菌木质纤维素降解中的酶组。接下来,我们关注两个系统中纤维小体的特性及其工程改造的可行性。最后,我们强调提高酶促木质纤维素降解效率的三个关键策略:发现新型木质纤维素分解物种和酶、对酶进行生物工程改造以提高热稳定性,以及在结构上优化设计的纤维小体。我们预计这些见解将为寻求提高木质纤维素作为生物燃料利用率的生物质领域提供资源。