Catalytic Mechanism of Human Alpha-galactosidase
Abstract
The enzyme {alpha}-galactosidase ({alpha}-GAL, also known as {alpha}-GAL A; E.C. 3.2.1.22) is responsible for the breakdown of {alpha}-galactosides in the lysosome. Defects in human {alpha}-GAL lead to the development of Fabry disease, a lysosomal storage disorder characterized by the buildup of {alpha}-galactosylated substrates in the tissues. {alpha}-GAL is an active target of clinical research: there are currently two treatment options for Fabry disease, recombinant enzyme replacement therapy (approved in the United States in 2003) and pharmacological chaperone therapy (currently in clinical trials). Previously, we have reported the structure of human {alpha}-GAL, which revealed the overall structure of the enzyme and established the locations of hundreds of mutations that lead to the development of Fabry disease. Here, we describe the catalytic mechanism of the enzyme derived from x-ray crystal structures of each of the four stages of the double displacement reaction mechanism. Use of a difluoro-{alpha}-galactopyranoside allowed trapping of a covalent intermediate. The ensemble of structures reveals distortion of the ligand into a {sup 1}S{sub 3} skew (or twist) boat conformation in the middle of the reaction cycle. The high resolution structures of each step in the catalytic cycle will allow for improved drug design efforts on {alpha}-GAL and other glycosidemore »
- Authors:
- Publication Date:
- Research Org.:
- Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
- Sponsoring Org.:
- DOE - OFFICE OF SCIENCE
- OSTI Identifier:
- 1019674
- Report Number(s):
- BNL-95520-2011-JA
Journal ID: ISSN 0021-9258; JBCHA3; TRN: US201115%%314
- DOE Contract Number:
- DE-AC02-98CH10886
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Biological Chemistry
- Additional Journal Information:
- Journal Volume: 285; Journal Issue: 6; Journal ID: ISSN 0021-9258
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 59 BASIC BIOLOGICAL SCIENCES; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; BREAKDOWN; BUILDUP; CRYSTAL STRUCTURE; CRYSTALLOGRAPHY; DEFECTS; DESIGN; ENZYMES; GLYCOSIDES; HYDROLASES; MUTATIONS; REACTION KINETICS; RESOLUTION; STORAGE; SUBSTRATES; TARGETS; THERAPY; TRAPPING; national synchrotron light source
Citation Formats
Guce, A, Clark, N, Salgado, E, Ivanen, D, Kulinskaya, A, Brumer, H, and Garman, S. Catalytic Mechanism of Human Alpha-galactosidase. United States: N. p., 2010.
Web.
Guce, A, Clark, N, Salgado, E, Ivanen, D, Kulinskaya, A, Brumer, H, & Garman, S. Catalytic Mechanism of Human Alpha-galactosidase. United States.
Guce, A, Clark, N, Salgado, E, Ivanen, D, Kulinskaya, A, Brumer, H, and Garman, S. 2010.
"Catalytic Mechanism of Human Alpha-galactosidase". United States.
@article{osti_1019674,
title = {Catalytic Mechanism of Human Alpha-galactosidase},
author = {Guce, A and Clark, N and Salgado, E and Ivanen, D and Kulinskaya, A and Brumer, H and Garman, S},
abstractNote = {The enzyme {alpha}-galactosidase ({alpha}-GAL, also known as {alpha}-GAL A; E.C. 3.2.1.22) is responsible for the breakdown of {alpha}-galactosides in the lysosome. Defects in human {alpha}-GAL lead to the development of Fabry disease, a lysosomal storage disorder characterized by the buildup of {alpha}-galactosylated substrates in the tissues. {alpha}-GAL is an active target of clinical research: there are currently two treatment options for Fabry disease, recombinant enzyme replacement therapy (approved in the United States in 2003) and pharmacological chaperone therapy (currently in clinical trials). Previously, we have reported the structure of human {alpha}-GAL, which revealed the overall structure of the enzyme and established the locations of hundreds of mutations that lead to the development of Fabry disease. Here, we describe the catalytic mechanism of the enzyme derived from x-ray crystal structures of each of the four stages of the double displacement reaction mechanism. Use of a difluoro-{alpha}-galactopyranoside allowed trapping of a covalent intermediate. The ensemble of structures reveals distortion of the ligand into a {sup 1}S{sub 3} skew (or twist) boat conformation in the middle of the reaction cycle. The high resolution structures of each step in the catalytic cycle will allow for improved drug design efforts on {alpha}-GAL and other glycoside hydrolase family 27 enzymes by developing ligands that specifically target different states of the catalytic cycle. Additionally, the structures revealed a second ligand-binding site suitable for targeting by novel pharmacological chaperones.},
doi = {},
url = {https://www.osti.gov/biblio/1019674},
journal = {Journal of Biological Chemistry},
issn = {0021-9258},
number = 6,
volume = 285,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 2010},
month = {Fri Jan 01 00:00:00 EST 2010}
}