Table 1. Panel of Protein Targets for Screening.

proteina	MWb	hitsc	nonpromiscuous hitsd	catalytic Cyse	Cys residuesf	possible therapeutic indicationsg
QSOX1	58084	0/993	0	noh	12	cancer53,54
PCAF	19452	0/993	0	no	3	HIV,55 cancer56,57
PBPR504C	57903	2/983	2	no	1	antibiotic resistance58
K-RasG12C	19245	10/968	7	no	3	cancer37,59
USP8	44429	20/923	7	yes	12	cancer,60 Cushing’s disease61
NNMT	31248	30/299	22	no	8	cancer,62 diet-induced obesity63
OTUB2	27312	47/938	42	yes	4	viral infection,64 diabetes,65 ALS66
NUDT7	26672	36/973	24	yes	4	diabetes67
NV3CP	19284	10/824	9	yes	5	viral infection68
BSA	66464	0/981	0	no	23	negative control

^aAcronyms are as follows: quiescin sulfhydryl oxidase 1 (QSOX1); penicillin-binding protein 3 (PBP); ubiquitin-specific peptidase 8 (USP8); nicotinamide N-methyltransferase (NNMT); norovirus 3C protease (NV3CP); bovine serum albumin (BSA).

^bMolecular weight of construct in Da.

^cNumber of fragments with >50% labeling/compounds for which labeling could be evaluated.

^dNumber of hits that did not label any other protein to >50%.

^eIndicates whether a catalytic cysteine is present in the protein.

^fNumber of cysteine residues in protein.

^gIndicates possible therapeutic rationale to inhibit this target.

^hQSOX1 contains a catalytic disulfide.