| Phylogenetic tree cluster affiliation | Number of clusters |
| α-Proteobacteria |
|
| Rhizobiaceae group | 3 |
| Acetobacteriaceae | 3 |
| Caulobacter group | 1 |
| Hyphomicrobium | 2 |
| No known cultivated relative (GenBank sequence(s) excluded from clusters) | 6 |
| Number of single sequences not in clusters: | 8 |
| β-Proteobacteria |
|
| Burkholderia group | 5 |
| Comamonadaceae | 2 |
| Spirallaceae | 1 |
| Nitrosomonadaceae | 2 |
| Rhodocyclus group | 1 |
| No known cultivated relative (GenBank sequence(s) excluded from clusters) | 5 |
| Number of single sequences not in clusters: | 3 |
| γ-Proteobacteria |
|
| Enterobacteriaceae | 2 |
| Pseudomonadaceae | 1 |
| Xanthomonas group | 2 |
| No known cultivated relative (GenBank sequence(s) excluded from clusters) | 2 |
| Number of single sequences not in clusters: | 3 |
| δ-Proteobacteria |
|
| Desulfuromonas group | 2 |
| Myxobacteria | 1 |
| No known cultivated relative (GenBank environmental sequence(s) in clusters) | 2 |
| Number of single sequences not in clusters: | 5 |
| CFB group |
|
| Flavobacteriaceae and Flexibacter group | 2 |
| Flavobacteriaceae and Cytophagaceae | 2 |
| Acidobacterium | 5 |
| Actinobacteria | 1 |
| Verrucomicrobia | 3 |