Quantitative analysis of inhibitor-induced assembly disruption in human UDP-GlcNAc 2-epimerase using mass photometry.

ABSTRACT: Uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) 2-epimerase (GNE)/N-acetylmannosamine kinase is the rate-limiting enzyme in sialic acid biosynthesis and a promising therapeutic target. We applied mass photometry (MP) to investigate GNE oligomerization and its modulation by three small-molecule inhibitors (C5, C13, and C15). Substrate-binding (UDP-GlcNAc) stabilized tetramer formation by increasing dimer-dimer affinity 98-fold. All inhibitors destabilized tetramers in a concentration-dependent manner, with IC₅₀ values in the low micromolar range. Using a modified Cheng-Prusoff equation, IC₅₀ values were converted into K_B,app values. Schild analysis and Operational Model of Allosterically Modulated Agonism were applied to estimate an apparent K_B,app

SUBMITTER: Boback N 

PROVIDER: S-EPMC12529881 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature