5DKX

Crystal structure of glucosidase II alpha subunit (Tris-bound from)

Summary for 5DKX

• Entry DOI: 10.2210/pdb5dkx/pdb
• Related: 5DKY 5DKZ 5DL0
• Descriptor: Alpha glucosidase-like protein, 2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL, CHLORIDE ION, ... (4 entities in total)
• Functional Keywords: endoplasmic reticulum, glycoside hydrolase, glycosylation, hydrolase
• Biological source: Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
• Total number of polymer chains: 1
• Total formula weight: 108694.21

Authors

Satoh, T.,Toshimori, T.,Yan, G.,Yamaguchi, T.,Kato, K. (deposition date: 2015-09-04, release date: 2016-01-27, Last modification date: 2024-03-20)

Primary citation

Satoh, T.,Toshimori, T.,Yan, G.,Yamaguchi, T.,Kato, K.
Structural basis for two-step glucose trimming by glucosidase II involved in ER glycoprotein quality control.
Sci Rep, 6:20575-20575, 2016

PubMed Abstract: The endoplasmic reticulum (ER) has a sophisticated protein quality control system for the efficient folding of newly synthesized proteins. In this system, a variety of N-linked oligosaccharides displayed on proteins serve as signals recognized by series of intracellular lectins. Glucosidase II catalyzes two-step hydrolysis at α1,3-linked glucose-glucose and glucose-mannose residues of high-mannose-type glycans to generate a quality control protein tag that is transiently expressed on glycoproteins and recognized by ER chaperones. Here we determined the crystal structures of the catalytic α subunit of glucosidase II (GIIα) complexed with two different glucosyl ligands containing the scissile bonds of first- and second-step reactions. Our structural data revealed that the nonreducing terminal disaccharide moieties of the two kinds of substrates can be accommodated in a gourd-shaped bilocular pocket, thereby providing a structural basis for substrate-binding specificity in the two-step deglucosylation catalyzed by this enzyme.

PubMed: 26847925
DOI: 10.1038/srep20575

Experimental method

X-RAY DIFFRACTION (1.4 Å)