Table 1 Applied substrates and expected enzyme conversion products.
From: Multiplex enzyme activity imaging by MALDI-IMS of substrate library conversions
Substrate peptide | Mass | Int. | Known target enzymes | Source (UniProt identifiers) | Product peptide 1 | Product mass 1 | Int. | Product peptide 2 | Product mass 2 | Int. | |
|---|---|---|---|---|---|---|---|---|---|---|---|
Proteases | |||||||||||
1 | GTPGPQGLLGAPGI | 1,234.42 | − | MMP | CA21_HUMAN (P08123); CA21_MOUSE (Q01149) | GTPGPQG | 612.64 | − | LLGAPGI | 639.80 | − |
2 | GDQGPPGIPGQPGF | 1,323.44 | − | MMP | CA14_HUMAN (P02462); CA54_HUMAN (P29400) | GDQGPPG | 626.62 | − | IPGQPGF | 714.82 | − |
3 | GLAQPVGINTSTTC | 1,361.52 | + | MMP | SY07_HUMAN (P80098) | GLAQPVG | 640.74 | − | INTSTTC | 738.81 | − |
4 | GQGPGPKRGTEPKV | 1,407.58 | +++ | Kallikrein-related peptidases | PCO1_HUMAN (Q15113) | GQGPGPK | 639.71 | + | RGTEPKV | 785.87 | + |
5 | KSYELPDGQVITIG | 1,519.71 | − | Caspase | IBP3_HUMAN (P17936); IBP3_PIG (P16611) | KSYELPD | 850.92 | − | GQVITIG | 686.79 | − |
6 | VSRLRAYLLPAPPA | 1,523.87 | ++ | MMP 2 | ACTA_HUMAN (P62736); ACTA_MOUSE (P62737) | VSRLRAY | 864.02 | + | LLAAPPA | 677.85 | + |
7 | AIQTVADGLKKQEE | 1,529.69 | + | Caspase | KRAC HUMAN (P31749) | AIQTVAD | 716.79 | − | GLKKQEE | 830.90 | + |
8 | PGFSPFRSSRIGEI | 1,549.77 | ++ | Kallikrein-related peptidases | KNG_HUMAN (P01042) | PGFSPFR | 806.92 | + | SSRIGEI | 760.85 | + |
9 | MGRGHARLVHVEEP | 1,587.81 | ++ | MMP | A2MG_HUMAN (P01023) | MGRGHAR | 783.91 | − | LVHVEEP | 821.90 | − |
10 | EQVADIDGQYAMTR | 1,596.73 | ++ | Caspase | CTNB_HUMAN (P35222); CTNB_MOUSE (Q02248) | EQVADID | 788.81 | − | GQYAMTR | 825.92 | − |
11 | LEERPAVMTSPLYL | 1,618.91 | +++ | MMP 2 | FGR1_HUMAN (P11362); FGR1_MOUSE (P16092) | LEERPAV | 812.92 | − | MTSPLYL | 823.99 | − |
12 | QFWSLAAPQRFGKK | 1,663.95 | ++ | Tissue plasminogen activator, t-PA | NPFF_HUMAN (O15130); NPFF_MOUSE (Q9WVA8) | QFWSLAA | 821.93 | + | PQRFGKK | 860.02 | + |
13 | RRPKPQQFFGLMGK | 1,690.05 | ++ | MMP 9 | TKN1_HUMAN (P20366); TKN1_MOUSE (P41539) | RRPKPQQ | 909.06 | − | FFGLMGK | 798.99 | − |
14 | YEVHHQKLVFFAED | 1,761.95 | + | MMP | A4_HUMAN (P05067); A4_RABIT (Q28748) | YEVHHQK | 940.03 | − | LVFFAED | 839.92 | − |
Kinases | |||||||||||
15 | RIRTQS*FSLQE | 1,364.53 | ++ | Kinases AKT1, CAMK2 | Nitric oxide synthase, endothelial | RIRTQSpFSLQE | 1,444.43 | + | |||
16 | ELQDDY*EDLLE | 1,381.41 | − | Kinases SYK, LYN | Band 3 anion transport protein | ELQDDYpEDLLE | 1,461.31 | − | |||
17 | NKRRGS*VPILR | 1,295.56 | +++ | Protein kinase A | Erythrocyte membrane protein band 4.2 | NKRRGSpVPILR | 1,375.46 | − | |||
18 | LLRGPS*WDPFR | 1,343.57 | ++ | Kinases MAPKAPK-2, PKG1 | Heat shock 27 kDa protein | LLRGPSpWDPFR | 1,423.47 | + | |||
Phosphatases | |||||||||||
19 | DADEYpLIPQQG | 1,327.00 | + | PTP1B, TC-PTP, SHP-2, Tyrosine | Epidermas growth factor receptor | DADEY*LIPQQG | 1,248.31 | ||||
20 | MCA-GDAEYpAAK(DNP)R | 1,530.55 | + | Protein Tyrosine Phosphatase Sigma-Aldrich: SCP0229 | MCA-GDAEY*AAK(DNP)R | 1,451.55 | + | ||||
