| Genus | Species Num | Strain Num | SOURCE |
|---|---|---|---|
| Hirschia | 1 | 1 | HMP |
| Histophilus | 1 | 1 | HMP |
| Hoeflea | 1 | 1 | HMP |
| Holdemanella | 1 | 2 | HMP/MGYG |
| Holdemania | 2 | 3 | HMP/MGYG |
| Hungatella | 2 | 4 | HMP/MGYG |
| Hydrogenivirga | 1 | 1 | HMP |
| Hydrogenobacter | 1 | 1 | HMP |
| Hydrogenobaculum | 1 | 1 | HMP |
| Hydrogenovibrio | 1 | 1 | HMP |