Table 1.
Analysis of QM and NEM modified cysteine containing peptides of Keap1a reacted with pNO-ASA.
| Identified peptide fragment (starting-ending residue) | Cys | % Modification | |
|---|---|---|---|
| QM | NEM | ||
| FLPLQSQCPEGAGDAVMYASTECK (16-39) | Cys23 | 19 | 81 |
| Cys38 | - | 100 | |
| LSQQLCDVTLQVK (72-84) | Cys77 | - | 100 |
| CVLHVMNGAVMYQIDSVVR (151-169) | Cys151 | - | 100 |
| ACSDFLVQQLDPSNAIGIANFAEQIGCVELHQR (170-202) | Cys171 | - | 100 |
| Cys196 | 14 | 86 | |
| QEEFFNLSHCQLVTLISR (217-234) | Cys226 | 28 | 72 |
| CESEVFHACINWVK (241-254) | Cys241 | - | 100 |
| Cys249 | 14 | 86 | |
| CHSLTPNFLQMQLQK (273-287) | Cys273 | 8 | 92 |
| IFEELTLHKPTQVMPCR (304-320) | Cys319 | 10 | 90 |
| SGLAGCVVGGLLYAVGGR (363-380) | Cys368 | - | 100 |
| NNSPDGNTDSSALDCYNPMTNQWSPCAPMS VPR (381-413) | Cys395 | - | 100 |
| Cys406 | - | 100 | |
| IGVGVIDGHIYAVGGSHGCIHHNSVER (416-442) | Cys434 | - | 100 |
| SGAGVCVLHNCIYAAGGYDGQDQLNSVER (508-536) | Cys513 | - | 100 |
| Cys518 | - | 100 | |
| IYVLGGYDGHTFLDSVECYDPDTDTWSEVTR (566-596) | Cys583 | - | 100 |
| SGVGVAVTMEPCR (602-614) | Cys613 | - | 100 |
a
Keap1 (15 μM) was incubated with pNO-ASA (30 μM) for 30 minutes followed by addition of NEM (20 mM) to trap unreacted free thiols.