School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea.
School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea.
Bioresour Technol. 2017 Sep;239:496-506. doi: 10.1016/j.biortech.2017.05.001. Epub 2017 May 4.
Complete hydrolysis of cellulose has been a key characteristic of biomass technology because of the limitation of industrial production hosts to use cellodextrin, the partial hydrolysis product of cellulose. Cellobiose, a β-1,4-linked glucose dimer, is a major cellodextrin of the enzymatic hydrolysis (via endoglucanase and exoglucanase) of cellulose. Conversion of cellobiose to glucose is executed by β-glucosidase. The complete extracellular hydrolysis of celluloses has several critical barriers in biomass technology. An alternative bioengineering strategy to make the bioprocessing less challenging is to engineer microbes with the abilities to hydrolyze and assimilate the cellulosic-hydrolysate cellodextrin. Microorganisms engineered to metabolize cellobiose rather than the monomeric glucose can provide several advantages for lignocellulose-based biorefineries. This review describes the recent advances and challenges in engineering efficient intracellular cellobiose metabolism in industrial hosts. This review also describes the limitations of and future prospectives in engineering intracellular cellobiose metabolism.
纤维素的完全水解一直是生物质技术的一个关键特征，因为工业生产宿主对使用纤维二糖（纤维素的部分水解产物）的限制。纤维二糖是纤维素酶解（通过内切葡聚糖酶和外切葡聚糖酶）的主要纤维二糖。β-葡萄糖苷酶将纤维二糖转化为葡萄糖。纤维素的完全细胞外水解在生物质技术中有几个关键障碍。一种使生物加工更具挑战性的替代生物工程策略是工程化具有水解和同化纤维素水解物纤维二糖能力的微生物。能够代谢纤维二糖而不是单体葡萄糖的微生物可以为基于木质纤维素的生物精炼厂提供几个优势。本文综述了在工业宿主中高效细胞内纤维二糖代谢工程的最新进展和挑战。本文还描述了工程化细胞内纤维二糖代谢的局限性和未来前景。
