Starch Synthesis in Ostreococcus tauri: The Starch-Binding Domains of Starch Synthase III-B Are Essential for Catalytic Activity.

ABSTRACT: Starch is the major energy storage carbohydrate in photosynthetic eukaryotes. Several enzymes are involved in building highly organized semi-crystalline starch granules, including starch-synthase III (SSIII), which is widely conserved in photosynthetic organisms. This enzyme catalyzes the extension of the α-1,4 glucan chain and plays a regulatory role in the synthesis of starch. Interestingly, unlike most plants, the unicellular green alga Ostreococcus tauri has three SSIII isoforms. In the present study, we describe the structure and function of OsttaSSIII-B, which has a similar modular organization to SSIII in higher plants, comprising three putative starch-binding domains (SBDs) at the N-terminal region and a C-terminal catalytic domain (CD). Purified recombinant OsttaSSIII-B dis

SUBMITTER: Barchiesi J 

PROVIDER: S-EPMC6210743 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature