Photosynthetic Sucrose Biosynthesis: An Evolutionary Perspective

Abstract

In this chapter, we explore the origins and evolutionary history of sucrose synthesis in plants. Our journey begins with the photosynthetic proteobacteria and cyanobacteria, which were probably the first organisms to synthesize this disaccharide sugar. Sucrose remained an obscure metabolite, used mainly for osmoregulation, until the endosymbiosis of a sucrose-synthesizing cyanobacterium gave rise to the chloroplasts of green plants. This unique event opened up new opportunities for sucrose, and ultimately led to its achieving global importance as one of the principal products of photosynthesis in plants. The rise of sucrose parallels the evolution of plants themselves, with the appearance of long distance vascular transport systems and the adoption of sucrose as a major transport sugar being key developments.