Unraveling A4GALT Mechanism and Its Modulation With Adamantyl‐Galactosylceramide Analogues: Advancing Fabry Disease Therapeutic Strategies
Abstract
ABSTRACT Fabry disease (FD), one of the most prevalent lysosomal storage disorders in Europe, is caused by mutations in the GLA gene leading to deficient α‐galactosidase A activity with lysosomal accumulation of globotriaosylceramide (Gb3). Enzyme replacement therapy (ERT) and pharmacological chaperone therapy (PCT) are used in the clinic to treat FD but are limited in efficacy, underscoring the need for alternative therapeutic strategies. Inhibiting α‐1,4‐galactosyltransferase (A4GALT), the glycosyltransferase responsible for Gb3 biosynthesis, represents an attractive strategy. Here, we reveal the molecular mechanism of human A4GALT at atomic detail using QM/MM simulations. We reveal a conformational rearrangement involving a 3 10 ‐helix that stabilizes the donor substrate and promotes a front‐face S N i‐like catalytic mechanism, in which a short‐lived oxocarbenium‐ion intermediate forms. The simulations informed the synthesis of a panel of glycosylceramide substrate analogues. Among these, AdaGalCer (Ada = adamantyl) proved able to reduce Gb3 production in fibroblasts while simultaneously being converted by A4GALT into the galactosylated product AdaGb2. These results provide a clear path towards inhibiting A4GALT, paving the way for potential new and effective FD therapeutics.
Article Details
Authors (14)
Nicky de Koster
Department of Medical Biochemistry and Department of Bio‐organic Synthesis Leiden Institute of Chemistry (LIC) Leiden University Leiden the Netherlands
Òscar Vidal‐Gironès
Departament De Química Inorgànica i Orgànica (Secció de Química Orgànica) and Institut de Química Teòrica i Computacional (IQTCUB) Universitat de Barcelona Barcelona Spain
Rowan de Graaf
Department of Medical Biochemistry and Department of Bio‐organic Synthesis Leiden Institute of Chemistry (LIC) Leiden University Leiden the Netherlands
Ken Kok
Department of Medical Biochemistry and Department of Bio‐organic Synthesis Leiden Institute of Chemistry (LIC) Leiden University Leiden the Netherlands
Lindsey T. Lelieveld
Department of Medical Biochemistry and Department of Bio‐organic Synthesis Leiden Institute of Chemistry (LIC) Leiden University Leiden the Netherlands
Jackelien Hoogervorst
Department of Medical Biochemistry and Department of Bio‐organic Synthesis Leiden Institute of Chemistry (LIC) Leiden University Leiden the Netherlands
Maria J. Ferraz
Department of Medical Biochemistry, Leiden Institute of Chemistry, Leiden University
José Pablo Rivas‐Fernández
Departament De Química Inorgànica i Orgànica (Secció de Química Orgànica) and Institut de Química Teòrica i Computacional (IQTCUB) Universitat de Barcelona Barcelona Spain
Rob F. Lammers
Department of Medical Biochemistry and Department of Bio‐organic Synthesis Leiden Institute of Chemistry (LIC) Leiden University Leiden the Netherlands
Herman S. Overkleeft
Leiden Institute of Chemistry
Johannes M. F. G. Aerts
Department of Medical Biochemistry, Leiden Institute of Chemistry, Leiden University
Rolf G. Boot
Department of Medical Biochemistry and Department of Bio‐organic Synthesis Leiden Institute of Chemistry (LIC) Leiden University Leiden the Netherlands
Carme Rovira
Departament de Química Inorgànica i Orgànica (Secció de Química Orgànica) and Institut de Química Teòrica i Computacional (IQTCUB)
Marta Artola
Department of Medical Biochemistry, Leiden Institute of Chemistry, Leiden University