Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors

The critical role of BACE-1 in the formation of neurotoxic ß-amyloid peptides in the brain makes it an attractive target for an efficacious treatment of Alzheimer’s disease. However, the development of clinically useful BACE-1 inhibitors has proven to be extremely challeng- ing. In this study we exa...

Full description

Bibliographic Details
Main Authors: Di Pietro, Ornella, Juarez-Jimenez, Jordi, Munoz-Torrero, Diego, Laughton, Charles A., Luque, F. Javier
Format: Article
Published: Public Library of Science 2017
Online Access:https://eprints.nottingham.ac.uk/42945/
_version_ 1848796607847333888
author Di Pietro, Ornella
Juarez-Jimenez, Jordi
Munoz-Torrero, Diego
Laughton, Charles A.
Luque, F. Javier
author_facet Di Pietro, Ornella
Juarez-Jimenez, Jordi
Munoz-Torrero, Diego
Laughton, Charles A.
Luque, F. Javier
author_sort Di Pietro, Ornella
building Nottingham Research Data Repository
collection Online Access
description The critical role of BACE-1 in the formation of neurotoxic ß-amyloid peptides in the brain makes it an attractive target for an efficacious treatment of Alzheimer’s disease. However, the development of clinically useful BACE-1 inhibitors has proven to be extremely challeng- ing. In this study we examine the binding mode of a novel potent inhibitor (compound 1, with IC50 80 nM) designed by synergistic combination of two fragments—huprine and rhein— that individually are endowed with very low activity against BACE-1. Examination of crystal structures reveals no appropriate binding site large enough to accommodate 1. Therefore we have examined the conformational flexibility of BACE-1 through extended molecular dynamics simulations, paying attention to the highly flexible region shaped by loops 8–14, 154–169 and 307–318. The analysis of the protein dynamics, together with studies of pocket druggability, has allowed us to detect the transient formation of a secondary binding site, which contains Arg307 as a key residue for the interaction with small molecules, at the edge of the catalytic cleft. The formation of this druggable “floppy” pocket would enable the bind- ing of multisite inhibitors targeting both catalytic and secondary sites. Molecular dynamics simulations of BACE-1 bound to huprine-rhein hybrid compounds support the feasibility of this hypothesis. The results provide a basis to explain the high inhibitory potency of the two enantiomeric forms of 1, together with the large dependence on the length of the oligo- methylenic linker. Furthermore, the multisite hypothesis has allowed us to rationalize the inhibitory potency of a series of tacrine-chromene hybrid compounds, specifically regarding the apparent lack of sensitivity of the inhibition constant to the chemical modifications intro- duced in the chromene unit. Overall, these findings pave the way for the exploration of novel functionalities in the design of optimized BACE-1 multisite inhibitors.
first_indexed 2025-11-14T19:50:41Z
format Article
id nottingham-42945
institution University of Nottingham Malaysia Campus
institution_category Local University
last_indexed 2025-11-14T19:50:41Z
publishDate 2017
publisher Public Library of Science
recordtype eprints
repository_type Digital Repository
spelling nottingham-429452020-05-04T18:45:52Z https://eprints.nottingham.ac.uk/42945/ Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors Di Pietro, Ornella Juarez-Jimenez, Jordi Munoz-Torrero, Diego Laughton, Charles A. Luque, F. Javier The critical role of BACE-1 in the formation of neurotoxic ß-amyloid peptides in the brain makes it an attractive target for an efficacious treatment of Alzheimer’s disease. However, the development of clinically useful BACE-1 inhibitors has proven to be extremely challeng- ing. In this study we examine the binding mode of a novel potent inhibitor (compound 1, with IC50 80 nM) designed by synergistic combination of two fragments—huprine and rhein— that individually are endowed with very low activity against BACE-1. Examination of crystal structures reveals no appropriate binding site large enough to accommodate 1. Therefore we have examined the conformational flexibility of BACE-1 through extended molecular dynamics simulations, paying attention to the highly flexible region shaped by loops 8–14, 154–169 and 307–318. The analysis of the protein dynamics, together with studies of pocket druggability, has allowed us to detect the transient formation of a secondary binding site, which contains Arg307 as a key residue for the interaction with small molecules, at the edge of the catalytic cleft. The formation of this druggable “floppy” pocket would enable the bind- ing of multisite inhibitors targeting both catalytic and secondary sites. Molecular dynamics simulations of BACE-1 bound to huprine-rhein hybrid compounds support the feasibility of this hypothesis. The results provide a basis to explain the high inhibitory potency of the two enantiomeric forms of 1, together with the large dependence on the length of the oligo- methylenic linker. Furthermore, the multisite hypothesis has allowed us to rationalize the inhibitory potency of a series of tacrine-chromene hybrid compounds, specifically regarding the apparent lack of sensitivity of the inhibition constant to the chemical modifications intro- duced in the chromene unit. Overall, these findings pave the way for the exploration of novel functionalities in the design of optimized BACE-1 multisite inhibitors. Public Library of Science 2017-05-15 Article PeerReviewed Di Pietro, Ornella, Juarez-Jimenez, Jordi, Munoz-Torrero, Diego, Laughton, Charles A. and Luque, F. Javier (2017) Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors. PLoS ONE, 12 (5). e0177683/1-e0177683/22. ISSN 1932-6203 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0177683 doi:10.1371/journal.pone.0177683 doi:10.1371/journal.pone.0177683
spellingShingle Di Pietro, Ornella
Juarez-Jimenez, Jordi
Munoz-Torrero, Diego
Laughton, Charles A.
Luque, F. Javier
Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors
title Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors
title_full Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors
title_fullStr Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors
title_full_unstemmed Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors
title_short Unveiling a novel transient druggable pocket in BACE-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors
title_sort unveiling a novel transient druggable pocket in bace-1 through molecular simulations: conformational analysis and binding mode of multisite inhibitors
url https://eprints.nottingham.ac.uk/42945/
https://eprints.nottingham.ac.uk/42945/
https://eprints.nottingham.ac.uk/42945/