TABLE 2.
MS/MS fragmentation analysis of acetylated odilorhabdin NOSO-95Ca
| NOSO-95C form and ion | m/z | Neutral loss from previous ion | Attribution | Assigned structure |
|---|---|---|---|---|
| NOSO-95C (m/z 1,265) | ||||
| [M + 2H]2+ | 633 | Lys-Dab(βOH)-Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt | ||
| y10 | 1,136.7 | 129 | Lys1 | Dab(βOH)-Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| y9 | 1,020.6 | 116 | Dab(βOH)2 | Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| 804.4 | 216 (128 + 88) | Lys10-Dbt11 | Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha | |
| y8 | 904.6 | 116 | Dab(βOH)3 | Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| 688.4 | 216 (128 + 88) | Lys10-Dbt11 | Gly-Orn-Pro-His-Lys-Dha | |
| y6 | 733.5 | 171 | Gly4-Orn5 | Pro-His-Lys-Dha-Lys-Dbt |
| 517.3 | 216 (128 + 88) | Lys10-Dbt11 | Pro-His-Lys-Dha | |
| b9 | 1,048.6 | 216 (128 + 88) | Lys10-Dbt11 | Lys- Dab(βOH)-Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha |
| Monoacetylated NOSO-95C (m/z 1,307) | ||||
| [M + 2H]2+ | 654 | Lys-Dab(βOH)-Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt | ||
| y10 | 1,178 | 129 | Lys1 | AcDab(βOH)-Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| y9 | 1,020.6 | 158 | AcDab(βOH)2 | Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| y8 | 904.6 | 116 | Dab(βOH)3 | Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| 688.4 | 216 (128 + 88) | Lys10-Dbt11 | Gly-Orn-Pro-His-Lys-Dha | |
| y6 | 733.5 | 171 | Gly4-Orn5 | Pro-His-Lys-Dha-Lys-Dbt |
| 517.3 | 216 (128 + 88) | Lys10-Dbt11 | Pro-His-Lys-Dha | |
| y5 | 635.9 | 97 | Pro9 | His-Lys-Dha-Lys-Dbt |
| b9 | 1,090.6 | 216 (128 + 88) | Lys10-Dbt11 | Lys-AcDab(βOH)-Dab(βOH)-Gly-Orn-Pro-His-Lys-Dha |
| Biacetylated NOSO-95C (m/z 1,349) | ||||
| [M + 2H]2+ | 675 | |||
| y10 | 1,220.7 | 129 | Lys1 | AcDab(βOH)-AcDab(βOH)-Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| y9 | 1,062.6 | 158 | AcDab(βOH)2 | AcDab(βOH)-Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| 846.4 | 216 (128 + 88) | Lys10-Dbt11 | AcDab(βOH)-Gly-Orn-Pro-His-Lys-Dha | |
| y8 | 904.6 | 158 | AcDab(βOH)3 | Gly-Orn-Pro-His-Lys-Dha-Lys-Dbt |
| 688.4 | 216 (128 + 88) | Lys10-Dbt11 | Gly-Orn-Pro-His-Lys-Dha | |
| y6 | 733.5 | 171 | Gly4-Orn5 | Pro-His-Lys-Dha-Lys-Dbt |
| 517.3 | 216 (128 + 88) | Lys10-Dbt11 | Pro-His-Lys-Dha | |
| b9 | 1,132.6 | 216 (128 + 88) | Lys10-Dbt11 | Lys-AcDab(βOH)-AcDab(βOH)-Gly-Orn-Pro-His-Lys-Dha |
| Triacetylated NOSO-95C (m/z 1,391) | ||||
| [M + 2H]2+ | 696 | |||
| y10 | 1,262.7 | 129 | Lys1 | AcDab(βOH)-AcDab(βOH)-Gly-Orn-Pro-His-Lys-Dha-AcLys-Dbt |
| 1,174.6 | 88 | Dbt | AcDab(βOH)-AcDab(βOH)-Gly-Orn-Pro-His-Lys-Dha-AcLys | |
| y9 | 1,104.6 | 158 | AcDab(βOH)2 | AcDab(βOH)-Gly-Orn-Pro-His-Lys-Dha-AcLys-Dbt |
| y8 | 946.6 | 158 | AcDab(βOH)3 | Gly-Orn-Pro-His-Lys-Dha-AcLys-Dbt |
| y6 | 775.5 | 171 | Gly4-Orn5 | Pro-His-Lys-Dha-AcLys-Dbt |
| 687.4 | 88 | Dbt | Pro-His-Lys-Dha-AcLys | |
| 517.3 | 170 | AcLys10 | Pro-His-Lys-Dha | |
| b9 | 1,132.6 | 258 (170 + 88) | AcLys10-Dbt11 | Lys-AcDab(βOH)-AcDab(βOH)-Gly-Orn-Pro-His-Lys-Dha |
a
See also Fig. S5. For bi- and triacetylated NOSO-95C, structures were retroactively assigned. Abbreviation: Ac, acetyl group.