Arai Munehito, Hayashi Yuuki, Kudo Hisashi
Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
Adv Exp Med Biol. 2018;1080:119-154. doi: 10.1007/978-981-13-0854-3_6.
Cyanobacterial biosynthesis of alkanes is an attractive way of producing substitutes for petroleum-based fuels. Key enzymes for bioalkane production in cyanobacteria are acyl-ACP reductase (AAR) and aldehyde-deformylating oxygenase (ADO). AAR catalyzes the reduction of the fatty acyl-ACP/CoA substrates to fatty aldehydes, which are then converted into alkanes/alkenes by ADO. These enzymes have been widely used for biofuel production by metabolic engineering of cyanobacteria and other organisms. However, both proteins, particularly ADO, have low enzymatic activities, and their catalytic activities are desired to be improved for use in biofuel production. Recently, progress has been made in the basic sciences and in the application of AAR and ADO in alkane production. This chapter provides an overview of recent advances in the study of the structure and function of AAR and ADO, protein engineering of these enzymes for improving activity and modifying substrate specificities, and examples of metabolic engineering of cyanobacteria and other organisms using AAR and ADO for biofuel production.
蓝藻细菌合成烷烃是生产石油基燃料替代品的一种有吸引力的方法。蓝藻细菌中生物烷烃生产的关键酶是酰基-ACP还原酶（AAR）和醛脱甲酰基加氧酶（ADO）。AAR催化脂肪酰基-ACP/辅酶A底物还原为脂肪醛，然后脂肪醛被ADO转化为烷烃/烯烃。这些酶已被广泛用于通过蓝藻细菌和其他生物体的代谢工程来生产生物燃料。然而，这两种蛋白质，尤其是ADO，酶活性较低，为用于生物燃料生产，它们的催化活性有待提高。最近，在基础科学以及AAR和ADO在烷烃生产中的应用方面都取得了进展。本章概述了AAR和ADO的结构与功能研究、通过蛋白质工程提高这些酶的活性并改变底物特异性的最新进展，以及利用AAR和ADO进行蓝藻细菌和其他生物体代谢工程以生产生物燃料的实例。
