Table 1.
Mass spectrometric analysis of StAR peptides
| Sequence residues | Digest peptide mass (M+H)+
|
||||
|---|---|---|---|---|---|
| Calculated | N-62 StAR | pH 8.0 band | pH 4.0 band I | pH 4.0 band II | |
| 249-253 | 600.351 | 600.354 | — | — | — |
| 112-118 | 713.420 | ||||
| 713.429 | 713.425 | 713.441 | — | ||
| 183-188 | 722.384 | 722.380 | 722.382 | — | |
| 722.402 | 722.397 | 722.394 | |||
| 133-140 | 1,050.547 | 1,050.548 | 1,050.550 | 1,050.515 | |
| 1,050.566 | 1,050.538 | 1,050.585 | 1,050.544 | ||
| 275-284 | 1,096.539 | 1,096.537 | — | — | — |
| 239-248 | 1,201.720 | 1,201.704 | — | — | — |
| 274-284 | 1,252.640 | 1,252.625 | — | — | — |
| 86-97 | 1,315.701 | 1,315.693 | 1,315.699 | — | |
| 1,315.683 | 1,315.693 | 1,315.705 | |||
| 122-132 met-ox | 1,330.668 | 1,330.659 | 1,330.665 | 1,330.612 | |
| 1,330.684 | 1,330.643 | 1,330.671 | 1,330.664 | ||
| 141-152 met-ox | 1,421.619 | — | — | ||
| 1,421.603 | 1,421.627 | ||||
| 141-152 met-ox2 | 1,437.614 | — | |||
| 1,437.593 | 1,437.581 | 1,437.661 | |||
| Leader (3-17)* | 1,717.682 | 1,717.681 | — | — | — |
| 218-236 met-ox | 2,018.979 | — | — | — | |
| 2,019.019 | |||||
| 163-182 | 2,082.062 | 2,082.076 | 2,082.065 | — | — |
| 2,082.054 | 2,082.029 | ||||
| 99-118 | 2,160.061 | — | — | ||
| 2,159.965 | 2,159.966 | ||||
| 99-118 met-ox | 2,176.056 | — | — | ||
| 2,175.984 | 2,175.996 | ||||
| 254-272 | 2,183.157 | 2,183.173 | — | — | — |
| 2,183.156 | |||||
| 194-213† | 2,207.918 | — | — | — | |
| 2.207.912 | |||||
| 193-213† | 2,364.019 | — | — | — | |
| 2,364.006 | |||||
| Leader (3-17)* + 63-85 met-ox | 4,448.881 | — | — | ||
| 4,449.007 | 4,449.019 | ||||
| Leader (3-17)* + 63-85 met-ox2 | 4,464.876 | — | — | ||
| 4,464.930 | 4,464.723 | ||||
| Leader (1-17)* + 63-85 met-ox3 | 4,768.012 | — | — | ||
| 4,767.900 | 4,767.886 | ||||
The top values are from MALDI MS and the bottom values are from liquid chromatography electrospray ionization MS.
*
Leader sequence (1-17) MRGSHHHHHHGSDDDDK.
†
Phosphorylated; met-ox: methionine sulfoxide residues.