All pairs of domain combinations at the superfamily level are listed here.
The identification of domain pairs does not account for the possibility of non-contiguous domains. Inserted, or interlaced, domains are seen as having a simple pair ordering.
The links below permit the addition or removal of specific sets of domain combination pairs.
Change the list of genome two-letter codes in the 'Include genomes' box to include domain-pairs from those genomes.
Change the list of genomes in the 'Exclude genomes' box to exclude domain-pairs from those genomes.
List of all two-letter genome codes.
| Superfamily (N) | Superfamily (C) | Number of occurrances | Number unique | |
|---|
| Carboxypeptidase regulatory domain-like | Porins | 34 | 5 |  |
| Sigma2 domain of RNA polymerase sigma factors | Sigma3 and sigma4 domains of RNA polymerase sigma factors | 18 | 2 | |
| P-loop containing nucleoside triphosphate hydrolases | P-loop containing nucleoside triphosphate hydrolases | 15 | 12 | |
| NAD(P)-binding Rossmann-fold domains | Glyceraldehyde-3-phosphate dehydrogenase-like, C-terminal domain | 13 | 3 | |
| Homodimeric domain of signal transducing histidine kinase | ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | 11 | 10 | |
| (Trans)glycosidases | Galactose-binding domain-like | 10 | 6 | |
| CheY-like | Homeodomain-like | 9 | 7 | |
| ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | CheY-like | 8 | 8 | |
| Galactose-binding domain-like | beta-Galactosidase/glucuronidase domain | 8 | 4 | |
| beta-Galactosidase/glucuronidase domain | (Trans)glycosidases | 8 | 4 | |
| Homodimeric domain of signal transducing histidine kinase | CheY-like | 7 | 7 | |
| Multidrug efflux transporter AcrB pore domain; PN1, PN2, PC1 and PC2 subdomains | Multidrug efflux transporter AcrB transmembrane domain | 6 | 4 | |
| Multidrug efflux transporter AcrB pore domain; PN1, PN2, PC1 and PC2 subdomains | Multidrug efflux transporter AcrB pore domain; PN1, PN2, PC1 and PC2 subdomains | 6 | 4 | |
| Formate/glycerate dehydrogenase catalytic domain-like | NAD(P)-binding Rossmann-fold domains | 6 | 2 | |
| Multidrug efflux transporter AcrB TolC docking domain; DN and DC subdomains | Multidrug efflux transporter AcrB transmembrane domain | 6 | 4 | |
| beta-N-acetylhexosaminidase-like domain | (Trans)glycosidases | 6 | 3 | |
| (Trans)glycosidases | Beta-D-glucan exohydrolase, C-terminal domain | 6 | 2 | |
| LuxS/MPP-like metallohydrolase | LuxS/MPP-like metallohydrolase | 6 | 3 | |
| Multidrug efflux transporter AcrB pore domain; PN1, PN2, PC1 and PC2 subdomains | Multidrug efflux transporter AcrB TolC docking domain; DN and DC subdomains | 6 | 4 | |
| Nucleotidylyl transferase | Anticodon-binding domain of a subclass of class I aminoacyl-tRNA synthetases | 6 | 6 | |
| ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | Homeodomain-like | 6 | 6 | |
| Multidrug efflux transporter AcrB transmembrane domain | Multidrug efflux transporter AcrB transmembrane domain | 6 | 4 | |
| Calcium-dependent phosphotriesterase | Homeodomain-like | 6 | 6 | |
| Multidrug resistance efflux transporter EmrE | Multidrug resistance efflux transporter EmrE | 6 | 2 | |
| Calcium-dependent phosphotriesterase | CheY-like | 6 | 6 | |
| P-loop containing nucleoside triphosphate hydrolases | Ribosomal protein S5 domain 2-like | 6 | 4 | |
| Calcium-dependent phosphotriesterase | ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | 6 | 6 | |
| Calcium-dependent phosphotriesterase | Calcium-dependent phosphotriesterase | 5 | 5 | |
| Aminoacid dehydrogenase-like, N-terminal domain | NAD(P)-binding Rossmann-fold domains | 5 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | EF-G C-terminal domain-like | 5 | 3 | |
| P-loop containing nucleoside triphosphate hydrolases | Translation proteins | 5 | 3 | |
| (Trans)glycosidases | Glycosyl hydrolase domain | 5 | 3 | |
| Multidrug efflux transporter AcrB TolC docking domain; DN and DC subdomains | Multidrug efflux transporter AcrB TolC docking domain; DN and DC subdomains | 5 | 3 | |
| MurD-like peptide ligases, catalytic domain | MurD-like peptide ligases, peptide-binding domain | 5 | 4 | |
| Calcium-dependent phosphotriesterase | Homodimeric domain of signal transducing histidine kinase | 5 | 5 | |
| Homodimeric domain of signal transducing histidine kinase | Homeodomain-like | 5 | 5 | |
| P-loop containing nucleoside triphosphate hydrolases | Homeodomain-like | 4 | 2 | |
| Actin-like ATPase domain | Actin-like ATPase domain | 4 | 1 | |
| PLP-binding barrel | Alanine racemase C-terminal domain-like | 4 | 3 | |
| Regulatory protein AraC | Homeodomain-like | 4 | 2 | |
| EF-G C-terminal domain-like | EF-G C-terminal domain-like | 4 | 2 | |
| Class II aaRS and biotin synthetases | Class II aaRS ABD-related | 4 | 4 | |
| ABC transporter transmembrane region | P-loop containing nucleoside triphosphate hydrolases | 4 | 2 | |
| NAD(P)-binding Rossmann-fold domains | 6-phosphogluconate dehydrogenase C-terminal domain-like | 4 | 2 | |
| PreATP-grasp domain | Glutathione synthetase ATP-binding domain-like | 4 | 2 | |
| Thiamin diphosphate-binding fold (THDP-binding) | Thiamin diphosphate-binding fold (THDP-binding) | 4 | 3 | |
| TPR-like | TPR-like | 4 | 4 | |
| PurM N-terminal domain-like | PurM C-terminal domain-like | 4 | 2 | |
| Nucleic acid-binding proteins | Class II aaRS and biotin synthetases | 4 | 4 | |
| Translation proteins | EF-G C-terminal domain-like | 4 | 2 | |
| Composite domain of metallo-dependent hydrolases | Metallo-dependent hydrolases | 3 | 2 | |
| P-loop containing nucleoside triphosphate hydrolases | "Winged helix" DNA-binding domain | 3 | 3 | |
| MurE/MurF N-terminal domain | MurD-like peptide ligases, peptide-binding domain | 3 | 2 | |
| PYP-like sensor domain (PAS domain) | ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | 3 | 3 | |
| Glutathione synthetase ATP-binding domain-like | Rudiment single hybrid motif | 3 | 1 | |
| Thiamin diphosphate-binding fold (THDP-binding) | TK C-terminal domain-like | 3 | 3 | |
| CheY-like | P-loop containing nucleoside triphosphate hydrolases | 3 | 1 | |
| Chondroitin AC/alginate lyase | Hyaluronate lyase-like, C-terminal domain | 3 | 2 | |
| Galactose-binding domain-like | Galactose mutarotase-like | 3 | 2 | |
| Translation proteins | Ribosomal protein S5 domain 2-like | 3 | 1 | |
| ValRS/IleRS/LeuRS editing domain | Nucleotidylyl transferase | 3 | 3 | |
| DPP6 N-terminal domain-like | alpha/beta-Hydrolases | 3 | 1 | |
| Calcium ATPase, transduction domain A | Calcium ATPase, transmembrane domain M | 3 | 3 | |
| PreATP-grasp domain | Rudiment single hybrid motif | 3 | 1 | |
| PDZ domain-like | ClpP/crotonase | 3 | 1 | |
| CBS-domain pair | FAD-binding/transporter-associated domain-like | 3 | 1 | |
| Calcium ATPase, transduction domain A | HAD-like | 3 | 3 | |
| "Winged helix" DNA-binding domain | Actin-like ATPase domain | 3 | 1 | |
| TrkA C-terminal domain-like | TrkA C-terminal domain-like | 3 | 2 | |
| ParB/Sulfiredoxin | KorB DNA-binding domain-like | 3 | 1 | |
| Nucleic acid-binding proteins | Nucleic acid-binding proteins | 3 | 3 | |
| MurE/MurF N-terminal domain | MurD-like peptide ligases, catalytic domain | 3 | 2 | |
| HAD-like | Calcium ATPase, transmembrane domain M | 3 | 3 | |
| Galactose mutarotase-like | Hyaluronate lyase-like, C-terminal domain | 3 | 2 | |
| EF-G C-terminal domain-like | Ribosomal protein S5 domain 2-like | 3 | 1 | |
| Chondroitin AC/alginate lyase | Galactose mutarotase-like | 3 | 2 | |
| Zinc beta-ribbon | DNA primase core | 3 | 2 | |
| PYP-like sensor domain (PAS domain) | Homodimeric domain of signal transducing histidine kinase | 3 | 3 | |
| Purple acid phosphatase, N-terminal domain | Metallo-dependent phosphatases | 3 | 1 | |
| ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | Ribosomal protein S5 domain 2-like | 3 | 2 | |
| Ribosomal protein S5 domain 2-like | Ribosomal protein S5 domain 2-like | 3 | 3 | |
| ValRS/IleRS/LeuRS editing domain | Anticodon-binding domain of a subclass of class I aminoacyl-tRNA synthetases | 3 | 3 | |
| Carbon-nitrogen hydrolase | Adenine nucleotide alpha hydrolases-like | 2 | 1 | |
| Riboflavin synthase domain-like | Ferredoxin reductase-like, C-terminal NADP-linked domain | 2 | 1 | |
| Zn-dependent exopeptidases | Bacterial exopeptidase dimerisation domain | 2 | 1 | |
| Starch-binding domain-like | Porins | 2 | 2 | |
| HD-domain/PDEase-like | Nucleotidyltransferase | 2 | 1 | |
| Lysozyme-like | beta-lactamase/transpeptidase-like | 2 | 2 | |
| Succinate dehydrogenase/fumarate reductase flavoprotein, catalytic domain | Succinate dehydrogenase/fumarate reductase flavoprotein C-terminal domain | 2 | 2 | |
| L30e-like | alpha/beta knot | 2 | 1 | |
| 4Fe-4S ferredoxins | 4Fe-4S ferredoxins | 2 | 2 | |
| Phosphoglucomutase, first 3 domains | Phosphoglucomutase, first 3 domains | 2 | 2 | |
| HD-domain/PDEase-like | ACT-like | 2 | 1 | |
| HD-domain/PDEase-like | TGS-like | 2 | 1 | |
| HMA, heavy metal-associated domain | HAD-like | 2 | 2 | |
| MurCD N-terminal domain | MurD-like peptide ligases, catalytic domain | 2 | 2 | |
| Tubulin nucleotide-binding domain-like | Tubulin C-terminal domain-like | 2 | 1 | |
| Galactose-binding domain-like | Chondroitin AC/alginate lyase | 2 | 1 | |
| tRNA-binding arm | Class II aaRS and biotin synthetases | 2 | 1 | |
| Ribosomal protein S5 domain 2-like | Type II DNA topoisomerase | 2 | 1 | |
| Homeodomain-like | Homeodomain-like | 2 | 1 | |
| NAD(P)-binding Rossmann-fold domains | LDH C-terminal domain-like | 2 | 1 | |
| Triger factor/SurA peptide-binding domain-like | FKBP-like | 2 | 2 | |
| Nucleotidyltransferase | TGS-like | 2 | 1 | |
| Ferritin-like | Rubredoxin-like | 2 | 1 | |
| ClpP/crotonase | ClpP/crotonase | 2 | 2 | |
| PKD domain | PKD domain | 2 | 2 | |
| CheY-like | C-terminal effector domain of the bipartite response regulators | 2 | 1 | |
| FAD/NAD(P)-binding domain | Succinate dehydrogenase/fumarate reductase flavoprotein C-terminal domain | 2 | 2 | |
| ThrRS/AlaRS common domain | Class II aaRS and biotin synthetases | 2 | 2 | |
| Nqo5-like | HydB/Nqo4-like | 2 | 1 | |
| Phosphoglucomutase, first 3 domains | Phosphoglucomutase, C-terminal domain | 2 | 2 | |
| FAD/NAD(P)-binding domain | Succinate dehydrogenase/fumarate reductase flavoprotein, catalytic domain | 2 | 2 | |
| 6-phosphogluconate dehydrogenase C-terminal domain-like | UDP-glucose/GDP-mannose dehydrogenase C-terminal domain | 2 | 1 | |
| Ribosomal protein S5 domain 2-like | GHMP Kinase, C-terminal domain | 2 | 1 | |
| Homeodomain-like | Tetracyclin repressor-like, C-terminal domain | 2 | 1 | |
| Cation efflux protein transmembrane domain-like | Cation efflux protein cytoplasmic domain-like | 2 | 1 | |
| Nucleic acid-binding proteins | RuvA domain 2-like | 2 | 2 | |
| beta-Galactosidase/glucuronidase domain | beta-Galactosidase/glucuronidase domain | 2 | 2 | |
| ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | Type II DNA topoisomerase | 2 | 1 | |
| Alpha-L RNA-binding motif | Pseudouridine synthase | 2 | 2 | |
| lambda repressor-like DNA-binding domains | Periplasmic binding protein-like I | 2 | 1 | |
| TGS-like | ACT-like | 2 | 1 | |
| DNA methylase specificity domain | DNA methylase specificity domain | 2 | 1 | |
| NAD(P)-binding Rossmann-fold domains | UDP-glucose/GDP-mannose dehydrogenase C-terminal domain | 2 | 1 | |
| Thiamin diphosphate-binding fold (THDP-binding) | DHS-like NAD/FAD-binding domain | 2 | 1 | |
| Penicillin binding protein dimerisation domain | beta-lactamase/transpeptidase-like | 2 | 2 | |
| NAD(P)-linked oxidoreductase | alpha-helical ferredoxin | 2 | 1 | |
| Galactose-binding domain-like | Hyaluronate lyase-like, C-terminal domain | 2 | 1 | |
| "Winged helix" DNA-binding domain | Periplasmic binding protein-like II | 2 | 1 | |
| Fe,Mn superoxide dismutase (SOD), N-terminal domain | Fe,Mn superoxide dismutase (SOD), C-terminal domain | 2 | 2 | |
| Translation proteins SH3-like domain | Nucleic acid-binding proteins | 2 | 2 | |
| Cobalamin (vitamin B12)-dependent enzymes | Cobalamin (vitamin B12)-binding domain | 2 | 1 | |
| Nucleotidyltransferase | ACT-like | 2 | 1 | |
| PurM C-terminal domain-like | PurM C-terminal domain-like | 1 | 1 | |
| S-adenosyl-L-methionine-dependent methyltransferases | Staphylococcal nuclease | 1 | 1 | |
| LysM domain | LysM domain | 1 | 1 | |
| GroEL equatorial domain-like | GroEL apical domain-like | 1 | 1 | |
| NAD(P)-binding Rossmann-fold domains | 1-deoxy-D-xylulose-5-phosphate reductoisomerase, C-terminal domain | 1 | 1 | |
| Fe,Mn superoxide dismutase (SOD), C-terminal domain | Rubredoxin-like | 1 | 1 | |
| Nucleic acid-binding proteins | Prokaryotic type KH domain (KH-domain type II) | 1 | 1 | |
| Aldolase | 2-isopropylmalate synthase LeuA, allosteric (dimerisation) domain | 1 | 1 | |
| GroEL equatorial domain-like | GroEL-intermediate domain like | 1 | 1 | |
| Fic-like | "Winged helix" DNA-binding domain | 1 | 1 | |
| N-terminal nucleophile aminohydrolases (Ntn hydrolases) | SIS domain | 1 | 1 | |
| Glutathione synthetase ATP-binding domain-like | Phosphohistidine domain | 1 | 1 | |
| ThrRS/AlaRS common domain | Class II aaRS ABD-related | 1 | 1 | |
| Nicotinate/Quinolinate PRTase N-terminal domain-like | Nicotinate/Quinolinate PRTase C-terminal domain-like | 1 | 1 | |
| MurCD N-terminal domain | MurD-like peptide ligases, peptide-binding domain | 1 | 1 | |
| Quinoprotein alcohol dehydrogenase-like | CheY-like | 1 | 1 | |
| Nucleotidyltransferase | Nucleotidyltransferase substrate binding subunit/domain | 1 | 1 | |
| Class II aaRS and biotin synthetases | GAD domain-like | 1 | 1 | |
| PUA domain-like | Ribosomal protein S5 domain 2-like | 1 | 1 | |
| Fibronectin type III | Pectin lyase-like | 1 | 1 | |
| MurD-like peptide ligases, catalytic domain | PLP-binding barrel | 1 | 1 | |
| GIY-YIG endonuclease | RuvA domain 2-like | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | Prokaryotic type KH domain (KH-domain type II) | 1 | 1 | |
| Quinoprotein alcohol dehydrogenase-like | ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | 1 | 1 | |
| Nucleic acid-binding proteins | BRCT domain | 1 | 1 | |
| Ribosomal L11/L12e N-terminal domain | Ribosomal protein L11, C-terminal domain | 1 | 1 | |
| MurE/MurF N-terminal domain | Alanine racemase C-terminal domain-like | 1 | 1 | |
| PUA domain-like | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| Arginyl-tRNA synthetase (ArgRS), N-terminal 'additional' domain | Anticodon-binding domain of a subclass of class I aminoacyl-tRNA synthetases | 1 | 1 | |
| PUA domain-like | alpha/beta knot | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | RecA protein, C-terminal domain | 1 | 1 | |
| PheT/TilS domain | Class II aaRS and biotin synthetases | 1 | 1 | |
| FAD/NAD(P)-binding domain | FAD-linked reductases, C-terminal domain | 1 | 1 | |
| 4Fe-4S ferredoxins | HydA/Nqo6-like | 1 | 1 | |
| CheY-like | Alkaline phosphatase-like | 1 | 1 | |
| HMA, heavy metal-associated domain | HMA, heavy metal-associated domain | 1 | 1 | |
| MurD-like peptide ligases, catalytic domain | Alanine racemase C-terminal domain-like | 1 | 1 | |
| Trigger factor ribosome-binding domain | Triger factor/SurA peptide-binding domain-like | 1 | 1 | |
| Class II aaRS and biotin synthetases | Putative anticodon-binding domain of alanyl-tRNA synthetase (AlaRS) | 1 | 1 | |
| Nucleotidylyl transferase | Ribosomal protein L25-like | 1 | 1 | |
| Methionine synthase domain | Cobalamin (vitamin B12)-binding domain | 1 | 1 | |
| Nucleic acid-binding proteins | Anticodon-binding domain of PheRS | 1 | 1 | |
| Nqo1 FMN-binding domain-like | alpha-helical ferredoxin | 1 | 1 | |
| TK C-terminal domain-like | Pyruvate-ferredoxin oxidoreductase, PFOR, domain III | 1 | 1 | |
| Transcription factor NusA, N-terminal domain | Prokaryotic type KH domain (KH-domain type II) | 1 | 1 | |
| GroEL-intermediate domain like | GroEL apical domain-like | 1 | 1 | |
| Carbamate kinase-like | PUA domain-like | 1 | 1 | |
| 2Fe-2S ferredoxin-like | alpha-helical ferredoxin | 1 | 1 | |
| RuvA domain 2-like | DNA helicase RuvA subunit, C-terminal domain | 1 | 1 | |
| CheY-like | Histidine-containing phosphotransfer domain, HPT domain | 1 | 1 | |
| Eukaryotic type KH-domain (KH-domain type I) | Nucleic acid-binding proteins | 1 | 1 | |
| RuvA domain 2-like | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| FabD/lysophospholipase-like | Probable ACP-binding domain of malonyl-CoA ACP transacylase | 1 | 1 | |
| Flavoproteins | 4Fe-4S ferredoxins | 1 | 1 | |
| Glutathione synthetase ATP-binding domain-like | Phosphoenolpyruvate/pyruvate domain | 1 | 1 | |
| Porins | Porins | 1 | 1 | |
| Formiminotransferase domain of formiminotransferase-cyclodeaminase. | Methenyltetrahydrofolate cyclohydrolase-like | 1 | 1 | |
| Mechanosensitive channel protein MscS (YggB), transmembrane region | Sm-like ribonucleoproteins | 1 | 1 | |
| FKBP-like | FKBP-like | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | TRCF domain-like | 1 | 1 | |
| Homocysteine S-methyltransferase | Dihydropteroate synthetase-like | 1 | 1 | |
| alpha/beta-Hydrolases | Galactose-binding domain-like | 1 | 1 | |
| CarD-like | TRCF domain-like | 1 | 1 | |
| Ribosomal protein S5 domain 2-like | Ribonuclease PH domain 2-like | 1 | 1 | |
| DNA ligase/mRNA capping enzyme, catalytic domain | RuvA domain 2-like | 1 | 1 | |
| Nucleic acid-binding proteins | DNA helicase RuvA subunit, C-terminal domain | 1 | 1 | |
| SIS domain | CBS-domain pair | 1 | 1 | |
| Acyl-CoA dehydrogenase NM domain-like | PG0775 C-terminal domain-like | 1 | 1 | |
| Homocysteine S-methyltransferase | Methionine synthase activation domain-like | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | Pre-protein crosslinking domain of SecA | 1 | 1 | |
| post-HMGL domain-like | Single hybrid motif | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | Glucocorticoid receptor-like (DNA-binding domain) | 1 | 1 | |
| N-terminal nucleophile aminohydrolases (Ntn hydrolases) | PRTase-like | 1 | 1 | |
| Dihydropteroate synthetase-like | Methionine synthase domain | 1 | 1 | |
| N-(deoxy)ribosyltransferase-like | TrpR-like | 1 | 1 | |
| Ribosomal protein S5 domain 2-like | Polynucleotide phosphorylase/guanosine pentaphosphate synthase (PNPase/GPSI), domain 3 | 1 | 1 | |
| Carbamate kinase-like | ACT-like | 1 | 1 | |
| Thioesterase/thiol ester dehydrase-isomerase | Thioesterase/thiol ester dehydrase-isomerase | 1 | 1 | |
| Anticodon-binding domain of a subclass of class I aminoacyl-tRNA synthetases | tRNA-binding arm | 1 | 1 | |
| Nucleic acid-binding proteins | GAD domain-like | 1 | 1 | |
| PIN domain-like | Ribonuclease H-like | 1 | 1 | |
| S-adenosyl-L-methionine-dependent methyltransferases | NAD(P)-binding Rossmann-fold domains | 1 | 1 | |
| Homocysteine S-methyltransferase | Cobalamin (vitamin B12)-binding domain | 1 | 1 | |
| HAMP domain-like | PYP-like sensor domain (PAS domain) | 1 | 1 | |
| Translation proteins | ThrRS/AlaRS common domain | 1 | 1 | |
| Class I glutamine amidotransferase-like | Adenine nucleotide alpha hydrolases-like | 1 | 1 | |
| PDZ domain-like | PDZ domain-like | 1 | 1 | |
| Ribonuclease PH domain 2-like | Ribonuclease PH domain 2-like | 1 | 1 | |
| Creatinase/prolidase N-terminal domain | Creatinase/aminopeptidase | 1 | 1 | |
| Nucleic acid-binding proteins | ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | 1 | 1 | |
| Methionyl-tRNA synthetase (MetRS), Zn-domain | Anticodon-binding domain of a subclass of class I aminoacyl-tRNA synthetases | 1 | 1 | |
| beta-N-acetylhexosaminidase-like domain | Galactose-binding domain-like | 1 | 1 | |
| Adenine nucleotide alpha hydrolases-like | Argininosuccinate synthetase, C-terminal domain | 1 | 1 | |
| Glutathione synthetase ATP-binding domain-like | Glutathione synthetase ATP-binding domain-like | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | Signal peptide-binding domain | 1 | 1 | |
| PIN domain-like | DNA/RNA polymerases | 1 | 1 | |
| Nucleic acid-binding proteins | S-adenosyl-L-methionine-dependent methyltransferases | 1 | 1 | |
| Nucleotidylyl transferase | tRNA-binding arm | 1 | 1 | |
| Prokaryotic type KH domain (KH-domain type II) | Ribosomal protein S3 C-terminal domain | 1 | 1 | |
| Glutathione synthetase ATP-binding domain-like | Methylglyoxal synthase-like | 1 | 1 | |
| LysM domain | Periplasmic binding protein-like I | 1 | 1 | |
| Metallo-dependent phosphatases | 5'-nucleotidase (syn. UDP-sugar hydrolase), C-terminal domain | 1 | 1 | |
| DNA ligase/mRNA capping enzyme, catalytic domain | Nucleic acid-binding proteins | 1 | 1 | |
| Insert subdomain of RNA polymerase alpha subunit | C-terminal domain of RNA polymerase alpha subunit | 1 | 1 | |
| PheT/TilS domain | Putative DNA-binding domain | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | C-terminal domain of alpha and beta subunits of F1 ATP synthase | 1 | 1 | |
| Methylated DNA-protein cysteine methyltransferase domain | Methylated DNA-protein cysteine methyltransferase, C-terminal domain | 1 | 1 | |
| Thiamin diphosphate-binding fold (THDP-binding) | Pyruvate-ferredoxin oxidoreductase, PFOR, domain III | 1 | 1 | |
| Folate-binding domain | Aminomethyltransferase beta-barrel domain | 1 | 1 | |
| Adenine nucleotide alpha hydrolases-like | GMP synthetase C-terminal dimerisation domain | 1 | 1 | |
| MurD-like peptide ligases, peptide-binding domain | Alanine racemase C-terminal domain-like | 1 | 1 | |
| "Winged helix" DNA-binding domain | HRDC-like | 1 | 1 | |
| N-utilization substance G protein NusG, N-terminal domain | Translation proteins SH3-like domain | 1 | 1 | |
| UDP-Glycosyltransferase/glycogen phosphorylase | UDP-Glycosyltransferase/glycogen phosphorylase | 1 | 1 | |
| Pyruvate-ferredoxin oxidoreductase, PFOR, domain III | 4Fe-4S ferredoxins | 1 | 1 | |
| Class II aaRS and biotin synthetases | Anticodon-binding domain of PheRS | 1 | 1 | |
| Metal cation-transporting ATPase, ATP-binding domain N | Calcium ATPase, transmembrane domain M | 1 | 1 | |
| Fibronectin type III | DNase I-like | 1 | 1 | |
| 4Fe-4S ferredoxins | FMN-dependent nitroreductase-like | 1 | 1 | |
| Duplicated hybrid motif | LysM domain | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | Restriction endonuclease-like | 1 | 1 | |
| Methionine synthase domain | Methionine synthase activation domain-like | 1 | 1 | |
| NagB/RpiA/CoA transferase-like | LmbE-like | 1 | 1 | |
| Class II aaRS and biotin synthetases | Translation proteins | 1 | 1 | |
| NAD(P)-binding Rossmann-fold domains | NAD(P)-binding Rossmann-fold domains | 1 | 1 | |
| Starch-binding domain-like | (Trans)glycosidases | 1 | 1 | |
| (Trans)glycosidases | Galactose mutarotase-like | 1 | 1 | |
| Nucleic acid-binding proteins | Putative DNA-binding domain | 1 | 1 | |
| Homodimeric domain of signal transducing histidine kinase | Histidine-containing phosphotransfer domain, HPT domain | 1 | 1 | |
| Cobalamin (vitamin B12)-binding domain | Methionine synthase activation domain-like | 1 | 1 | |
| DNA ligase/mRNA capping enzyme, catalytic domain | BRCT domain | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | FtsH protease domain-like | 1 | 1 | |
| Aldolase | Single hybrid motif | 1 | 1 | |
| LexA/Signal peptidase | LexA/Signal peptidase | 1 | 1 | |
| TrmE connector domain | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| Ribonuclease PH domain 2-like | Nucleic acid-binding proteins | 1 | 1 | |
| Metallo-dependent phosphatases | Quinoprotein alcohol dehydrogenase-like | 1 | 1 | |
| Periplasmic binding protein-like II | ACT-like | 1 | 1 | |
| Mechanosensitive channel protein MscS (YggB), transmembrane region | Mechanosensitive channel protein MscS (YggB), C-terminal domain | 1 | 1 | |
| HMA, heavy metal-associated domain | Calcium ATPase, transmembrane domain M | 1 | 1 | |
| TK C-terminal domain-like | 4Fe-4S ferredoxins | 1 | 1 | |
| Double Clp-N motif | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| Cysteine proteinases | Invasin/intimin cell-adhesion fragments | 1 | 1 | |
| Nucleic acid-binding proteins | PheT/TilS domain | 1 | 1 | |
| IlvD/EDD N-terminal domain-like | LeuD/IlvD-like | 1 | 1 | |
| Dihydrofolate reductase-like | Cytidine deaminase-like | 1 | 1 | |
| Chaperone J-domain | DnaJ/Hsp40 cysteine-rich domain | 1 | 1 | |
| Calcium ATPase, transduction domain A | Metal cation-transporting ATPase, ATP-binding domain N | 1 | 1 | |
| Enolase N-terminal domain-like | Enolase C-terminal domain-like | 1 | 1 | |
| PK beta-barrel domain-like | PK C-terminal domain-like | 1 | 1 | |
| ThrRS/AlaRS common domain | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| Penicillin binding protein dimerisation domain | Penicillin-binding protein 2x (pbp-2x), c-terminal domain | 1 | 1 | |
| Polynucleotide phosphorylase/guanosine pentaphosphate synthase (PNPase/GPSI), domain 3 | Nucleic acid-binding proteins | 1 | 1 | |
| PreATP-grasp domain | PreATP-grasp domain | 1 | 1 | |
| Sm-like ribonucleoproteins | Mechanosensitive channel protein MscS (YggB), C-terminal domain | 1 | 1 | |
| C-terminal UvrC-binding domain of UvrB | RuvA domain 2-like | 1 | 1 | |
| Fibronectin type III | His-Me finger endonucleases | 1 | 1 | |
| Glyceraldehyde-3-phosphate dehydrogenase-like, C-terminal domain | 1-deoxy-D-xylulose-5-phosphate reductoisomerase, C-terminal domain | 1 | 1 | |
| Carbamoyl phosphate synthetase, large subunit connection domain | Methylglyoxal synthase-like | 1 | 1 | |
| Domain of the SRP/SRP receptor G-proteins | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| PreATP-grasp domain | Methylglyoxal synthase-like | 1 | 1 | |
| Fe,Mn superoxide dismutase (SOD), N-terminal domain | Rubredoxin-like | 1 | 1 | |
| Aldolase | Chorismate mutase II | 1 | 1 | |
| PIN domain-like | 5' to 3' exonuclease, C-terminal subdomain | 1 | 1 | |
| Mss4-like | Peptide methionine sulfoxide reductase | 1 | 1 | |
| Ribonuclease PH domain 2-like | Eukaryotic type KH-domain (KH-domain type I) | 1 | 1 | |
| CorA soluble domain-like | Magnesium transport protein CorA, transmembrane region | 1 | 1 | |
| Clc chloride channel | CBS-domain pair | 1 | 1 | |
| PheT/TilS domain | Anticodon-binding domain of PheRS | 1 | 1 | |
| Ribosomal protein S5 domain 2-like | Eukaryotic type KH-domain (KH-domain type I) | 1 | 1 | |
| Homocysteine S-methyltransferase | Methionine synthase domain | 1 | 1 | |
| MurE/MurF N-terminal domain | PLP-binding barrel | 1 | 1 | |
| Ribonuclease PH domain 2-like | Polynucleotide phosphorylase/guanosine pentaphosphate synthase (PNPase/GPSI), domain 3 | 1 | 1 | |
| S-adenosyl-L-methionine-dependent methyltransferases | DNA methylase specificity domain | 1 | 1 | |
| Chondroitin AC/alginate lyase | Chondroitin AC/alginate lyase | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | post-AAA+ oligomerization domain-like | 1 | 1 | |
| Thiolase-like | Thiolase-like | 1 | 1 | |
| 5' to 3' exonuclease, C-terminal subdomain | Ribonuclease H-like | 1 | 1 | |
| Dihydropteroate synthetase-like | Cobalamin (vitamin B12)-binding domain | 1 | 1 | |
| Carbamoyl phosphate synthetase, small subunit N-terminal domain | Class I glutamine amidotransferase-like | 1 | 1 | |
| lambda repressor-like DNA-binding domains | LexA/Signal peptidase | 1 | 1 | |
| Trypsin-like serine proteases | Trypsin-like serine proteases | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | HRDC-like | 1 | 1 | |
| Insert subdomain of RNA polymerase alpha subunit | RBP11-like subunits of RNA polymerase | 1 | 1 | |
| Ribonuclease H-like | DNA/RNA polymerases | 1 | 1 | |
| Pre-protein crosslinking domain of SecA | Helical scaffold and wing domains of SecA | 1 | 1 | |
| HMA, heavy metal-associated domain | Calcium ATPase, transduction domain A | 1 | 1 | |
| Anticodon-binding domain of a subclass of class I aminoacyl-tRNA synthetases | Nucleic acid-binding proteins | 1 | 1 | |
| E set domains | Glycosyl hydrolase domain | 1 | 1 | |
| Polynucleotide phosphorylase/guanosine pentaphosphate synthase (PNPase/GPSI), domain 3 | Eukaryotic type KH-domain (KH-domain type I) | 1 | 1 | |
| Phosphoenolpyruvate/pyruvate domain | PK C-terminal domain-like | 1 | 1 | |
| DnaJ/Hsp40 cysteine-rich domain | HSP40/DnaJ peptide-binding domain | 1 | 1 | |
| CBS-domain pair | Inosine monophosphate dehydrogenase (IMPDH) | 1 | 1 | |
| HAMP domain-like | Homodimeric domain of signal transducing histidine kinase | 1 | 1 | |
| Phosphohistidine domain | Phosphoenolpyruvate/pyruvate domain | 1 | 1 | |
| RuvA domain 2-like | BRCT domain | 1 | 1 | |
| PEP carboxykinase N-terminal domain | PEP carboxykinase-like | 1 | 1 | |
| GreA transcript cleavage protein, N-terminal domain | FKBP-like | 1 | 1 | |
| PurM C-terminal domain-like | Class I glutamine amidotransferase-like | 1 | 1 | |
| ACT-like | ACT-like | 1 | 1 | |
| FAD-binding/transporter-associated domain-like | Uridine diphospho-N-Acetylenolpyruvylglucosamine reductase, MurB, C-terminal domain | 1 | 1 | |
| Ribosomal protein L7/12, oligomerisation (N-terminal) domain | ClpS-like | 1 | 1 | |
| Galactose mutarotase-like | Six-hairpin glycosidases | 1 | 1 | |
| Nucleotide-diphospho-sugar transferases | Guanosine diphospho-D-mannose pyrophosphorylase/mannose-6-phosphate isomerase linker domain | 1 | 1 | |
| S-adenosyl-L-methionine-dependent methyltransferases | Putative methyltransferase TM0872, insert domain | 1 | 1 | |
| GIY-YIG endonuclease | C-terminal UvrC-binding domain of UvrB | 1 | 1 | |
| DNA/RNA polymerases | Lesion bypass DNA polymerase (Y-family), little finger domain | 1 | 1 | |
| Chaperone J-domain | HSP40/DnaJ peptide-binding domain | 1 | 1 | |
| Methionyl-tRNA synthetase (MetRS), Zn-domain | Nucleic acid-binding proteins | 1 | 1 | |
| Metal cation-transporting ATPase, ATP-binding domain N | HAD-like | 1 | 1 | |
| ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | DNA mismatch repair protein MutL | 1 | 1 | |
| Periplasmic binding protein-like II | GlnB-like | 1 | 1 | |
| NAD(P)-binding Rossmann-fold domains | TrkA C-terminal domain-like | 1 | 1 | |
| Quinoprotein alcohol dehydrogenase-like | Calcium-dependent phosphotriesterase | 1 | 1 | |
| ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | Histidine-containing phosphotransfer domain, HPT domain | 1 | 1 | |
| Transcription factor NusA, N-terminal domain | Nucleic acid-binding proteins | 1 | 1 | |
| FAD/NAD(P)-binding domain | HI0933 insert domain-like | 1 | 1 | |
| Ribosomal protein S5 domain 2-like | Nucleic acid-binding proteins | 1 | 1 | |
| Formyltransferase | FMT C-terminal domain-like | 1 | 1 | |
| Obg GTP-binding protein N-terminal domain | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| Putative DNA-binding domain | Class II aaRS and biotin synthetases | 1 | 1 | |
| UBA-like | Elongation factor Ts (EF-Ts), dimerisation domain | 1 | 1 | |
| PreATP-grasp domain | Carbamoyl phosphate synthetase, large subunit connection domain | 1 | 1 | |
| Carboxypeptidase regulatory domain-like | Metallo-dependent phosphatases | 1 | 1 | |
| N-terminal domain of DnaB helicase | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| Aldolase | post-HMGL domain-like | 1 | 1 | |
| PKD domain | L domain-like | 1 | 1 | |
| Nucleotidylyl transferase | Alpha-L RNA-binding motif | 1 | 1 | |
| Quinoprotein alcohol dehydrogenase-like | Homeodomain-like | 1 | 1 | |
| Acyl-CoA dehydrogenase C-terminal domain-like | PG0775 C-terminal domain-like | 1 | 1 | |
| Class II aaRS ABD-related | C-terminal domain of ProRS | 1 | 1 | |
| NagB/RpiA/CoA transferase-like | NagB/RpiA/CoA transferase-like | 1 | 1 | |
| Trypsin-like serine proteases | PDZ domain-like | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | CarD-like | 1 | 1 | |
| Class I glutamine amidotransferase-like | GMP synthetase C-terminal dimerisation domain | 1 | 1 | |
| PurM N-terminal domain-like | PurM N-terminal domain-like | 1 | 1 | |
| Translation proteins | PRC-barrel domain | 1 | 1 | |
| HMA, heavy metal-associated domain | Homeodomain-like | 1 | 1 | |
| 2,3-Bisphosphoglycerate-independent phosphoglycerate mutase, substrate-binding domain | Alkaline phosphatase-like | 1 | 1 | |
| RuvA domain 2-like | RuvA domain 2-like | 1 | 1 | |
| HSP40/DnaJ peptide-binding domain | HSP40/DnaJ peptide-binding domain | 1 | 1 | |
| Putative anticodon-binding domain of alanyl-tRNA synthetase (AlaRS) | ThrRS/AlaRS common domain | 1 | 1 | |
| DNA clamp | DNA clamp | 1 | 1 | |
| C-terminal domain of transcriptional repressors | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| S-adenosyl-L-methionine-dependent methyltransferases | P-loop containing nucleoside triphosphate hydrolases | 1 | 1 | |
| Lysozyme-like | LysM domain | 1 | 1 | |
| Methionyl-tRNA synthetase (MetRS), Zn-domain | Nucleotidylyl transferase | 1 | 1 | |
| Prokaryotic type KH domain (KH-domain type II) | Prokaryotic type KH domain (KH-domain type II) | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | EF-Tu/eEF-1alpha/eIF2-gamma C-terminal domain | 1 | 1 | |
| Oligoxyloglucan reducing end-specific cellobiohydrolase | Pectin lyase-like | 1 | 1 | |
| HAD-like | Ribosomal protein S5 domain 2-like | 1 | 1 | |
| Sigma3 and sigma4 domains of RNA polymerase sigma factors | Sigma3 and sigma4 domains of RNA polymerase sigma factors | 1 | 1 | |
| HisI-like | all-alpha NTP pyrophosphatases | 1 | 1 | |
| Nucleotidylyl transferase | Nucleic acid-binding proteins | 1 | 1 | |
| DnaK suppressor protein DksA, alpha-hairpin domain | Glucocorticoid receptor-like (DNA-binding domain) | 1 | 1 | |
| Translation proteins | EF-Tu/eEF-1alpha/eIF2-gamma C-terminal domain | 1 | 1 | |
| PUA domain-like | S-adenosyl-L-methionine-dependent methyltransferases | 1 | 1 | |
| HlyD-like secretion proteins | HlyD-like secretion proteins | 1 | 1 | |
| PK beta-barrel domain-like | Phosphoenolpyruvate/pyruvate domain | 1 | 1 | |
| HAMP domain-like | ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase | 1 | 1 | |
| Dihydropteroate synthetase-like | Methionine synthase activation domain-like | 1 | 1 | |
| Peptidase/esterase 'gauge' domain | alpha/beta-Hydrolases | 1 | 1 | |
| Arginyl-tRNA synthetase (ArgRS), N-terminal 'additional' domain | Nucleotidylyl transferase | 1 | 1 | |
| Molybdenum cofactor biosynthesis proteins | CinA-like | 1 | 1 | |
| E set domains | (Trans)glycosidases | 1 | 1 | |
| Metallo-hydrolase/oxidoreductase | Flavoproteins | 1 | 1 | |
| Adenine nucleotide alpha hydrolases-like | DHS-like NAD/FAD-binding domain | 1 | 1 | |
| S-adenosylmethionine synthetase | S-adenosylmethionine synthetase | 1 | 1 | |
| "Winged helix" DNA-binding domain | NagB/RpiA/CoA transferase-like | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | Class I glutamine amidotransferase-like | 1 | 1 | |
| MurD-like peptide ligases, peptide-binding domain | PLP-binding barrel | 1 | 1 | |
| Formiminotransferase domain of formiminotransferase-cyclodeaminase. | Formiminotransferase domain of formiminotransferase-cyclodeaminase. | 1 | 1 | |
| RBP11-like subunits of RNA polymerase | C-terminal domain of RNA polymerase alpha subunit | 1 | 1 | |
| Putative anticodon-binding domain of alanyl-tRNA synthetase (AlaRS) | Translation proteins | 1 | 1 | |
| Zn-dependent exopeptidases | Fibronectin type III | 1 | 1 | |
| Ribosomal protein S5 domain 2-like | DNA mismatch repair protein MutL | 1 | 1 | |
| RuvA domain 2-like | MCP/YpsA-like | 1 | 1 | |
| Fibronectin type III | Quinoprotein alcohol dehydrogenase-like | 1 | 1 | |
| Concanavalin A-like lectins/glucanases | PLC-like phosphodiesterases | 1 | 1 | |
| Acyl-CoA N-acyltransferases (Nat) | Acyl-CoA N-acyltransferases (Nat) | 1 | 1 | |
| L9 N-domain-like | Ribosomal protein L9 C-domain | 1 | 1 | |
| Putative DNA-binding domain | Anticodon-binding domain of PheRS | 1 | 1 | |
| Adenine nucleotide alpha hydrolases-like | PheT/TilS domain | 1 | 1 | |
| DNA-glycosylase | Nudix | 1 | 1 | |
| ValRS/IleRS/LeuRS editing domain | tRNA-binding arm | 1 | 1 | |
| "Winged helix" DNA-binding domain | GntR ligand-binding domain-like | 1 | 1 | |
| Starch-binding domain-like | Starch-binding domain-like | 1 | 1 | |
| beta-Galactosidase/glucuronidase domain | Galactose mutarotase-like | 1 | 1 | |
| PYP-like sensor domain (PAS domain) | CheY-like | 1 | 1 | |
| 5' to 3' exonuclease, C-terminal subdomain | DNA/RNA polymerases | 1 | 1 | |
| 4'-phosphopantetheinyl transferase | 4'-phosphopantetheinyl transferase | 1 | 1 | |
| Glutathione synthetase ATP-binding domain-like | Carbamoyl phosphate synthetase, large subunit connection domain | 1 | 1 | |
| beta-lactamase/transpeptidase-like | Penicillin-binding protein 2x (pbp-2x), c-terminal domain | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | C-terminal UvrC-binding domain of UvrB | 1 | 1 | |
| P-loop containing nucleoside triphosphate hydrolases | Helical scaffold and wing domains of SecA | 1 | 1 | |
| Riboflavin synthase domain-like | Riboflavin synthase domain-like | 1 | 1 | |
| FAD/NAD(P)-binding domain | FAD/NAD-linked reductases, dimerisation (C-terminal) domain | 1 | 1 | |
| Class II aaRS and biotin synthetases | C-terminal domain of ProRS | 1 | 1 | |
| dsRNA-binding domain-like | Ribosomal protein S5 domain 2-like | 1 | 1 | |
| Nucleotidylyl transferase | TPR-like | 1 | 1 | |
| Ribosomal protein S5 domain 2-like | Thioesterase/thiol ester dehydrase-isomerase | 1 | 1 | |
| Thiamin diphosphate-binding fold (THDP-binding) | 4Fe-4S ferredoxins | 1 | 1 | |
| SGNH hydrolase | Metallo-dependent phosphatases | 1 | 1 | |
| Radical SAM enzymes | RuvA domain 2-like | 1 | 1 | |
| L domain-like | L domain-like | 1 | 1 | |
| Phospholipase D/nuclease | Phospholipase D/nuclease | 1 | 1 | |
| PurM N-terminal domain-like | Class I glutamine amidotransferase-like | 1 | 1 | |
| Six-hairpin glycosidases | PLC-like phosphodiesterases | 1 | 1 | |
| Acyl-CoA dehydrogenase NM domain-like | Acyl-CoA dehydrogenase C-terminal domain-like | 1 | 1 | |
