Donated Chemical Probes

Target	PARK7
Targeted domain	Active site (covalent binding to Cys106)
Mode of action	Covalent inhibitor
Control	MB078
Recommended cellular usage concentration	≤ 1 µM
In vivo use	No
Donated by	Leiden University Medical Center
Developed by Leiden University Medical Center in the Framework of:

Inhibitor/agonist potency: goal is < 100 nM (IC₅₀, K_d)	DiFMUAc assay: IC₅₀ = 19 nM (Activity assay that relies on the deacetylation of the fluorogenic substrate 6,8-difluoro-4-methylumbelliferyl (DiFMUAc)). Irreversible covalent binding to Cys106: k_inact/KI = 12093 M‐1s‐1, k_inact = 0.052 s‐1, KI(app) = 4.3 μM FP (Fluorescence Polarization) assay: IC₅₀ = 100 nM
Selectivity within target family: > 30-fold	Not determined for peptidase C56 family; within carbonic anhydrases (CA) superfamily: no inhibition of DUBs observed (UCHL1: IC₅₀ = 18.96 µM (using Ub-RhoMorpholine as substrate.))
Selectivity outside target family	SLC-ABPP experiment (cysteine activity-based protein profiling): no off-targets detected. Only PARK7 Cys106 peptide detected among >5000 Cys sites in A549 cells.
On target cell activity for cell-based targets: goal is < 1 µM IC₅₀/EC₅₀	ABPP assay: Full inhibition at a JYQ-173 concentration of < 1 μM (1h, 37°C).
Control compound (100 times less potent than the probe)	MB078: DiFMUAc assay (IC₅₀ = 2.24 µM (118 x )), FP assay (IC₅₀ = 3.6 µM (36 x)