Improved Production of Plant Isoquinoline Alkaloids by Metabolic Engineering

Abstract

Higher plants produce diverse low-molecular-weight chemicals such as alkaloids, terpenoids and phenylpropanoid compounds. Among these chemicals, alkaloids are particularly important in medicine due to their high biological activities. However, the low yield of metabolites, especially alkaloids, in plants limits large-scale development of the plant natural product industry. In this chapter, I describe the metabolic engineering of plants to improve the yield and quality of useful secondary metabolites and their potentials. Among alkaloids, I focus on the production of isoquinoline alkaloids (IQAs), as their biosynthesis has been most intensively studied at the molecular level and their application in metabolic engineering has also been intensively examined. Based on our understanding of IQA engineering, I discuss its application to the production of other alkaloids through similar approaches.