| Gene | Description | Domains | Gene lists |
|---|---|---|---|
| Spis_XP_022784740_1 | — | E1_FCCH, FHA, MtrF-like_dom-III | — |
| Spis_XP_022792135_1 | ubiquitin-like modifier activating enzyme 1 | BilD_C, E1_4HB, E1_FCCH, E1_UFD, ThiF, UBA_E1_SCCH | — |
| Spis_XP_022795514_1 | ubiquitin-like modifier activating enzyme 6 | E1_4HB, E1_FCCH, E1_UFD, ThiF, UBA_E1_SCCH | — |