The Structure of Maltooctaose-Bound Escherichia coli Branching Enzyme Suggests a Mechanism for Donor Chain Specificity.

ABSTRACT: Glycogen is the primary storage polysaccharide in bacteria and animals. It is a glucose polymer linked by α-1,4 glucose linkages and branched via α-1,6-linkages, with the latter reaction catalyzed by branching enzymes. Both the length and dispensation of these branches are critical in defining the structure, density, and relative bioavailability of the storage polysaccharide. Key to this is the specificity of branching enzymes because they define branch length. Herein, we report the crystal structure of the maltooctaose-bound branching enzyme from the enterobacteria E. coli. The structure identifies three new malto-oligosaccharide binding sites and confirms oligosaccharide binding in seven others, bringing the total number of oligosaccharide binding sites to twelve. In addition, the

SUBMITTER: Fawaz R 

PROVIDER: S-EPMC10254366 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature