1HCU

alpha-1,2-mannosidase from Trichoderma reesei

Summary for 1HCU

• Entry DOI: 10.2210/pdb1hcu/pdb
• Descriptor: ALPHA-1,2-MANNOSIDASE, 2-acetamido-2-deoxy-beta-D-glucopyranose, CALCIUM ION, ... (4 entities in total)
• Functional Keywords: glycosylation, glycosyl hydrolase
• Biological source: TRICHODERMA REESEI
• Total number of polymer chains: 4
• Total formula weight: 219810.83

Authors

Van Petegem, F.,Contreras, H.,Contreras, R.,Van Beeumen, J. (deposition date: 2001-05-09, release date: 2001-10-18, Last modification date: 2024-10-09)

Primary citation

Van Petegem, F.,Contreras, H.,Contreras, R.,Van Beeumen, J.
Trichoderma Reesei Alpha-1,2-Mannosidase: Structural Basis for the Cleavage of Four Consecutive Mannose Residues
J.Mol.Biol., 312:157-, 2001

PubMed Abstract: The process of N-glycosylation of eukaryotic proteins involves a range of host enzymes that delete or add saccharide monomers. While endoplasmic reticulum (E.R.) mannosidases cleave only one mannose to produce the Man8B isomer, an alpha-1,2-mannosidase from Trichoderma reesei can sequentially cleave all four 1,2-linked mannose sugars from a Man(9)GlcNAc(2) oligosaccharide, a feature reminiscent of the activity of Golgi mannosidases. We now report the structure of the T. reesei enzyme at 2.37 A resolution. The enzyme folds as an (alpha alpha)(7) barrel. The substrate-binding site of the T. reesei mannosidase differs appreciably from the Saccharomyces cerevisiae enzyme. In the former, shorter loops at the surface allow substrate protein to come closer to the catalytic site. There is more internal space available, so that different oligosaccharide conformations are sterically allowed in the T. reesei alpha-1,2-mannosidase.

PubMed: 11545593
DOI: 10.1006/JMBI.2001.4946

Experimental method

X-RAY DIFFRACTION (2.37 Å)