5FIH

SACCHAROMYCES CEREVISIAE GAS2P (E176Q MUTANT) IN COMPLEX WITH LAMINARITETRAOSE AND LAMINARIPENTAOSE

Summary for 5FIH

• Entry DOI: 10.2210/pdb5fih/pdb
• Descriptor: 1,3-BETA-GLUCANOSYLTRANSFERASE, beta-D-glucopyranose-(1-3)-beta-D-glucopyranose-(1-3)-beta-D-glucopyranose-(1-3)-alpha-D-glucopyranose, beta-D-glucopyranose-(1-3)-beta-D-glucopyranose-(1-3)-alpha-D-glucopyranose-(1-3)-beta-D-glucopyranose-(1-3)-beta-D-glucopyranose, ... (4 entities in total)
• Functional Keywords: transferase
• Biological source: SACCHAROMYCES CEREVISIAE
• Total number of polymer chains: 1
• Total formula weight: 63922.28

Authors

Raich, L.,Borodkin, V.,van Aalten, D.M.F.,Hurtado-Guerrero, R.,Rovira, C. (deposition date: 2015-09-25, release date: 2016-02-17, Last modification date: 2024-11-06)

Primary citation

Raich, L.,Borodkin, V.,Fang, W.,Castro-Lopez, J.,van Aalten, D.M.,Hurtado-Guerrero, R.,Rovira, C.
A Trapped Covalent Intermediate of a Glycoside Hydrolase on the Pathway to Transglycosylation. Insights from Experiments and Quantum Mechanics/Molecular Mechanics Simulations.
J. Am. Chem. Soc., 138:3325-3332, 2016

PubMed Abstract: The conversion of glycoside hydrolases (GHs) into transglycosylases (TGs), i.e., from enzymes that hydrolyze carbohydrates to enzymes that synthesize them, represents a promising solution for the large-scale synthesis of complex carbohydrates for biotechnological purposes. However, the lack of knowledge about the molecular details of transglycosylation hampers the rational design of TGs. Here we present the first crystallographic structure of a natural glycosyl-enzyme intermediate (GEI) of Saccharomyces cerevisiae Gas2 in complex with an acceptor substrate and demonstrate, by means of quantum mechanics/molecular mechanics metadynamics simulations, that it is tuned for transglycosylation (ΔG(⧧) = 12 kcal/mol). The 2-OH···nucleophile interaction is found to be essential for catalysis: its removal raises the free energy barrier significantly (11 and 16 kcal/mol for glycosylation and transglycosylation, respectively) and alters the conformational itinerary of the substrate (from (4)C1 → [(4)E](⧧) → (1,4)B/(4)E to (4)C1 → [(4)H3](⧧) → (4)C1). Our results suggest that changes in the interactions involving the 2-position could have an impact on the transglycosylation activity of several GHs.

PubMed: 26859322
DOI: 10.1021/jacs.5b10092

Experimental method

X-RAY DIFFRACTION (1.8 Å)