Jung Sang-Kyu, Parisutham Vinuselvi, Jeong Seong Hun, Lee Sung Kuk
School of Nano-Bioscience and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea.
J Biomed Biotechnol. 2012;2012:405842. doi: 10.1155/2012/405842. Epub 2012 Jul 15.
A major technical challenge in the cost-effective production of cellulosic biofuel is the need to lower the cost of plant cell wall degrading enzymes (PCDE), which is required for the production of sugars from biomass. Several competitive, low-cost technologies have been developed to produce PCDE in different host organisms such as Escherichia coli, Zymomonas mobilis, and plant. Selection of an ideal host organism is very important, because each host organism has its own unique features. Synthetic biology-aided tools enable heterologous expression of PCDE in recombinant E. coli or Z. mobilis and allow successful consolidated bioprocessing (CBP) in these microorganisms. In-planta expression provides an opportunity to simplify the process of enzyme production and plant biomass processing and leads to self-deconstruction of plant cell walls. Although the future of currently available technologies is difficult to predict, a complete and viable platform will most likely be available through the integration of the existing approaches with the development of breakthrough technologies.
纤维素生物燃料经济高效生产中的一个主要技术挑战是需要降低植物细胞壁降解酶（PCDE）的成本，这种酶是从生物质中生产糖所必需的。已经开发了几种具有竞争力的低成本技术，用于在不同的宿主生物体中生产PCDE，如大肠杆菌、运动发酵单胞菌和植物。选择理想的宿主生物体非常重要，因为每种宿主生物体都有其独特的特征。合成生物学辅助工具能够在重组大肠杆菌或运动发酵单胞菌中实现PCDE的异源表达，并使这些微生物能够成功进行联合生物加工（CBP）。植物体内表达为简化酶生产和植物生物质加工过程提供了机会，并导致植物细胞壁的自我解构。尽管目前可用技术的未来难以预测，但通过将现有方法与突破性技术的开发相结合，很可能会出现一个完整且可行的平台。
