(A, B) Gel-based ABPP assays with WT and S111A human ABHD14B, showing robust dose dependent activity of WT ABHD14B, but not S111A ABHD14B, as a function of increasing: (A) enzyme concentration (0.5 – 10 μM), and (B) activity probe (FP-Rh) concentration (0.2 – 5 μM), while keeping the other constant (activity probe concentration (5 μM) in A; enzyme concentration (5 μM) in B). The gel-based ABPP experiments were done three independent times with reproducible results each time. (C) Colorimetric enzymatic assay showing ~ 10-fold more activity of WT human ABHD14B, compared to S111A human ABHD14B, against pNp-acetate (500 μM). The colorimetric assays were done three independent times with reproducible results each time.