7EKX image
Entry Detail
PDB ID:
7EKX
Title:
Crystal Structure of the Candida Glabrata Glycogen Debranching Enzyme (W470A E564Q) in complex with maltononaose
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2021-04-07
Release Date:
2021-11-10
Method Details:
Experimental Method:
Resolution:
3.40 Å
R-Value Free:
0.30
R-Value Work:
0.27
R-Value Observed:
0.27
Space Group:
C 2 2 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:4-alpha-glucanotransferase
Mutations:W470A, E564Q
Chain IDs:A, B
Chain Length:1536
Number of Molecules:2
Biological Source:Candida glabrata CBS 138
Ligand Molecules
Primary Citation
Crystal structures of glycogen-debranching enzyme mutants in complex with oligosaccharides.
Acta Crystallogr.,Sect.F 77 420 426 (2021)
PMID: 34726181 DOI: 10.1107/S2053230X21010918

Abstact

Debranching is a critical step in the mobilization of the important energy store glycogen. In eukaryotes, including fungi and animals, the highly conserved glycogen-debranching enzyme (GDE) debranches glycogen by a glucanotransferase (GT) reaction followed by a glucosidase (GC) reaction. Previous work indicated that these reactions are catalyzed by two active sites located more than 50 Å apart and provided insights into their catalytic mechanisms and substrate recognition. Here, five crystal structures of GDE in complex with oligosaccharides with 4-9 glucose residues are presented. The data suggest that the glycogen main chain plays a critical role in binding to the GT and GC active sites of GDE and that a minimum of five main-chain residues are required for optimal binding.

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Primary Citation of related structures