Table 3.
Agent | [Alcohol] µMa |
AGGC | Residue Photolabeled |
Peptideb | Charge | Rt, min | Xcorr | MH+c | Accuracyd ppm |
---|---|---|---|---|---|---|---|---|---|
3-azibutanol | 100 | + | E193 | [1] | +3 | 23.45 | 5.29 | 2437.60 | 2.46 |
100 | – | Photolabeled peptide not detected | |||||||
3-azibutanol | 100 | + | E163 | [2] | +2 | 22.52 | 5.06 | 1824.96 | 3.28 |
100 | – | Photolabeled peptide not detected | |||||||
3-azioctanol | 10 | + | E163 | [2] | +2 | 18.82 | 2.95 | 1880.90 | 0.00 |
10 | – | [2] | +2 | 18.84 | 4.30 | 1880.90 | 0.00 | ||
Unlabeled peptide f | – | E193 | [1] | +3 | 16.15 | 4.77 | 2365.54 | 0.00 | |
– | E163 | [2] | +2 | 21.02 | 4.75 | 1752.89 | 0.00 |
Lowest 3-azialcohol concentration where photoincorporation was detected.
Peptides photolabeled by 3-azialcohols: [1]=RhoGDIα(181–199)=FTDDDKTDHLSWEWNLTIK; [2]= RhoGDIα(153–167)=AEEYEFLTPVEEAPK. Photolabeled residues are indicated in bold.
Representative observed masses which include increases due to photolabeling by 3-azioctanol (128 Dalton) or 3-azibutanol (72 Dalton).
Accuracy is the difference between the calculated and observed mass expressed in ppm.
Unlabeled peptides are those derived from that fraction of RhoGDIα which was not photolabeled during the experiment with 100 µM azibutanol in the presence of AGGC. See “EXPERIMENTAL PROCEDURES” section for other details