| Protein | species | pdb code | Family of trans. regulators | z1 | Rmsd (amino acids)2 | Sequence identity over equivalent region (%) |
| IclR | E. coli | 1TD5 | IclR | 36.8 | 0 (171) | 100 |
| Glyoxylate regulatory protein | E. coli | 1TF1 | IclR | 26.9 | 1.4 (168) | 44 |
| IclR homologue | Thermotoga maritima | 1MKM | IclR | 24.3 | 1.9 (166) | 31 |
| YaiJ | E. coli | 1YSQ | IclR | 24.1 | 1.6 (167) | 28 |
| KdgR | E. coli | 1YSP | IclR | 22.4 | 1.9 (159) | 30 |
| 3’5’ cyclic nucleotide phosphodiesterase (containing GAF domain) | E. coli | 1MC0 | - | 9.3 | 2.7 (111) | 12 |
| GAF domain from cyclic nucleotide phosphodiesterase | S. cerevisae | 1F5M | - | 8.5 | 2.7 (113) | 11 |
| Gaf domains from adenylyl cyclase | 1YKD | - | 7.8 | 2.6 (107) | 11 | |
| Profilin | Arabidopsis thaliana | 3NUL | - | 6.4 | 3.1 (99) | 5 |