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1505  structures 8864  species 0  interactions 277454  sequences 4764  architectures

Clan: Thiolase (CL0046)


Thiolase-like Superfamily Add an annotation

Thiolases are ubiquitous and form a large superfamily. Thiolases can function either degradatively, in the beta-oxidation pathway of fatty acids, or biosynthetically. Biosynthetic thiolases catalyse the formation of acetoacetyl-CoA from two molecules of acetyl-CoA . This is one of the fundamental categories of carbon skeletal assembly patterns in biological systems and is the first step in a wide range of biosynthetic pathways [1]. Thiolase are usually dimeric or tetrameric enzymes. Within each monomer there are two similar domains related by pseudo dyad. The N-terminal of these two domains contains a large insertion of about 100 amino acids.

This clan contains 14 families and the total number of domains in the clan is 277454. The clan was built by RD Finn.

Literature references

  1. Modis Y, Wierenga RK; , Structure Fold Des 1999;7:1279-1290.: A biosynthetic thiolase in complex with a reaction intermediate: the crystal structure provides new insights into the catalytic mechanism. PUBMED:10545327 EPMC:10545327


This clan contains the following 14 member families:

ACP_syn_III ACP_syn_III_C Chal_sti_synt_C Chal_sti_synt_N FAE1_CUT1_RppA HMG_CoA_synt_C HMG_CoA_synt_N KAsynt_C_assoc ketoacyl-synt Ketoacyl-synt_2 Ketoacyl-synt_C SpoVAD Thiolase_C Thiolase_N

External database links

Domain organisation

Below is a listing of the unique domain organisations or architectures from this clan. More...

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The table below shows the number of occurrences of each domain throughout the sequence database. More...

Pfam family Num. domains Alignment
ketoacyl-synt (PF00109) 55189 (19.9%) View
Ketoacyl-synt_C (PF02801) 52050 (18.8%) View
Thiolase_N (PF00108) 44259 (16.0%) View
Thiolase_C (PF02803) 42413 (15.3%) View
KAsynt_C_assoc (PF16197) 23783 (8.6%) View
ACP_syn_III_C (PF08541) 19586 (7.1%) View
ACP_syn_III (PF08545) 14759 (5.3%) View
Chal_sti_synt_N (PF00195) 5433 (2.0%) View
Chal_sti_synt_C (PF02797) 5416 (2.0%) View
FAE1_CUT1_RppA (PF08392) 4847 (1.7%) View
HMG_CoA_synt_C (PF08540) 3957 (1.4%) View
HMG_CoA_synt_N (PF01154) 3405 (1.2%) View
SpoVAD (PF07451) 1372 (0.5%) View
Ketoacyl-synt_2 (PF13723) 985 (0.4%) View
Total: 14 Total: 277454 Clan alignment

Please note: Clan alignments can be very large and can cause problems for some browsers. Read the note above before viewing.

Family relationships

This diagram shows the relationships between members of this clan. More...

Species distribution

Tree controls


This tree shows the occurrence of the domains in this clan across different species. More...



For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the MSD group, to allow us to map Pfam domains onto UniProt three-dimensional structures. The table below shows the mapping between the Pfam families in this clan, the corresponding UniProt entries, and the region of the three-dimensional structures that are available for that sequence.

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