| Genus | Species Num | Strain Num | SOURCE |
|---|---|---|---|
| Blastopirellula | 1 | 1 | HMP |
| Blattabacterium | 1 | 1 | HMP |
| Blautia | 7 | 11 | HMP/MGYG |
| Bordetella | 5 | 5 | HMP |
| Borrelia | 4 | 4 | HMP |
| Borreliella | 4 | 6 | HMP |
| Brachybacterium | 1 | 1 | HMP |
| Brachyspira | 3 | 4 | HMP/MGYG |
| Bradyrhizobium | 3 | 3 | HMP |
| Brevibacillus | 2 | 2 | HMP/MGYG |