Summary: Thiolase, C-terminal domain
This is the Wikipedia entry entitled "Beta-ketoacyl-ACP synthase". More...
Does Pfam agree with the content of the Wikipedia entry ?
Editing Wikipedia articles
Before you edit for the first time
You should take a few minutes to view the following pages:
How your contribution will be recorded
Beta-ketoacyl-ACP synthase Edit Wikipedia article
|3-oxoacyl-ACP synthase, mitochondrial|
|Locus||Chr. 3 p24.2|
|Beta-ketoacyl synthase, N-terminal domain|
|the crystal structure of beta-ketoacyl-[acyl carrier protein] synthase ii from streptococcus pneumoniae, triclinic form|
|Beta-ketoacyl synthase, C-terminal domain|
|arabidopsis thaliana mitochondrial beta-ketoacyl acp synthase hexanoic acid complex|
It is the enzyme that catalyses the condensation of malonyl-ACP with the growing fatty acid chain. It is found as a component of a number of enzymatic systems, including fatty acid synthetase (FAS), which catalyses the formation of long-chain fatty acids from acetyl-CoA, malonyl-CoA and NADPH; the multi-functional 6-methysalicylic acid synthase (MSAS) from Penicillium patulum, which is involved in the biosynthesis of a polyketide antibiotic; polyketide antibiotic synthase enzyme systems; Emericella nidulans multifunctional protein Wa, which is involved in the biosynthesis of conidial green pigment; Rhizobium nodulation protein nodE, which probably acts as a beta-ketoacyl synthase in the synthesis of the nodulation Nod factor fatty acyl chain; and yeast mitochondrial protein CEM1. The condensation reaction is a two step process, first the acyl component of an activated acyl primer is transferred to a cysteine residue of the enzyme and is then condensed with an activated malonyl donor with the concomitant release of carbon dioxide.
Beta-ketoacyl synthase contains two protein domains. The active site is located between the N- and C-terminal domains. The N-terminal domain contains most of the structures involved in dimer formation and also the active site cysteine. Residues from both domains contribute to substrate binding and catalysis
 See also
- Kauppinen S, Siggaard-Andersen M, von Wettstein-Knowles P (1988). "beta-Ketoacyl-ACP synthase I of Escherichia coli: nucleotide sequence of the fabB gene and identification of the cerulenin binding residue". Carlsberg Res. Commun. 53 (6): 357–70. PMID 3076376.
- Beck J, Ripka S, Siegner A, Schiltz E, Schweizer E (September 1990). "The multifunctional 6-methylsalicylic acid synthase gene of Penicillium patulum. Its gene structure relative to that of other polyketide synthases". Eur. J. Biochem. 192 (2): 487–98. doi:10.1111/j.1432-1033.1990.tb19252.x. PMID 2209605.
- Huang W, Jia J, Edwards P, Dehesh K, Schneider G, Lindqvist Y (1998). "Crystal structure of beta-ketoacyl-acyl carrier protein synthase II from E.coli reveals the molecular architecture of condensing enzymes.". EMBO J 17 (5): 1183–91. doi:10.1093/emboj/17.5.1183. PMC 1170466. PMID 9482715. //www.ncbi.nlm.nih.gov/pmc/articles/PMC1170466/.
|This transferase article is a stub. You can help Wikipedia by expanding it.|
Thiolase, C-terminal domain Provide feedback
Thiolase is reported to be structurally related to beta-ketoacyl synthase (PF00109), and also chalcone synthase.
Mathieu M, Modis Y, Zeelen JP, Engel CK, Abagyan RA, Ahlberg A, Rasmussen B, Lamzin VS, Kunau WH, Wierenga RK; , J Mol Biol 1997;273:714-728.: The 1.8 A crystal structure of the dimeric peroxisomal 3-ketoacyl-CoA thiolase of Saccharomyces cerevisiae: implications for substrate binding and reaction mechanism. PUBMED:9402066 EPMC:9402066
Internal database links
|Similarity to PfamA using HHSearch:||Ketoacyl-synt_C ACP_syn_III_C|
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR020617
Two different types of thiolase [PUBMED:1755959, PUBMED:2191949, PUBMED:1354266] are found both in eukaryotes and in prokaryotes: acetoacetyl-CoA thiolase (EC) and 3-ketoacyl-CoA thiolase (EC). 3-ketoacyl-CoA thiolase (also called thiolase I) has a broad chain-length specificity for its substrates and is involved in degradative pathways such as fatty acid beta-oxidation. Acetoacetyl-CoA thiolase (also called thiolase II) is specific for the thiolysis of acetoacetyl-CoA and involved in biosynthetic pathways such as poly beta-hydroxybutyrate synthesis or steroid biogenesis.
In eukaryotes, there are two forms of 3-ketoacyl-CoA thiolase: one located in the mitochondrion and the other in peroxisomes.
There are two conserved cysteine residues important for thiolase activity. The first located in the N-terminal section of the enzymes is involved in the formation of an acyl-enzyme intermediate; the second located at the C-terminal extremity is the active site base involved in deprotonation in the condensation reaction.
Mammalian nonspecific lipid-transfer protein (nsL-TP) (also known as sterol carrier protein 2) is a protein which seems to exist in two different forms: a 14 Kd protein (SCP-2) and a larger 58 Kd protein (SCP-x). The former is found in the cytoplasm or the mitochondria and is involved in lipid transport; the latter is found in peroxisomes. The C-terminal part of SCP-x is identical to SCP-2 while the N-terminal portion is evolutionary related to thiolases [PUBMED:1755959].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Molecular function||transferase activity, transferring acyl groups other than amino-acyl groups (GO:0016747)|
|Biological process||metabolic process (GO:0008152)|
- the number of sequences which exhibit this architecture
a textual description of the architecture, e.g. Gla, EGF x 2, Trypsin.
This example describes an architecture with one
Gladomain, followed by two consecutive
EGFdomains, and finally a single
- the UniProt description of the protein sequence
- the number of residues in the sequence
- the Pfam graphic itself.
Loading domain graphics...
We make a range of alignments for each Pfam-A family:
- the curated alignment from which the HMM for the family is built
- the alignment generated by searching the sequence database using the HMM
- Representative Proteomes (RPs) at 15%, 35%, 55% and 75% co-membership thresholds
- alignment generated by searching the NCBI sequence database using the family HMM
- alignment generated by searching the metagenomics sequence database using the family HMM
You can see the alignments as HTML or in three different sequence viewers:
- Pfam viewer
- an HTML-based viewer that uses DAS to retrieve alignment fragments on request
1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
Format an alignment
If you find these logos useful in your own work, please consider citing the following article:
Note: You can also download the data file for the tree.
Curation and family details
|Author:||Sonnhammer ELL, Griffiths-Jones SR|
|Number in seed:||22|
|Number in full:||14316|
|Average length of the domain:||125.10 aa|
|Average identity of full alignment:||38 %|
|Average coverage of the sequence by the domain:||31.49 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||13|
|Download:||download the raw HMM for this family|
Weight segments by...
Change the size of the sunburst
selected sequences to HMM
a FASTA-format file
- 0 sequences
- 0 species
How the sunburst is generated
Colouring and labels
Anomalies in the taxonomy tree
Missing taxonomic levels
Unmapped species names
Too many species/sequences
The tree shows the occurrence of this domain across different species. More...
You can use the tree controls to manipulate how the interactive tree is displayed:
- show/hide the summary boxes
- highlight species that are represented in the seed alignment
- expand/collapse the tree or expand it to a given depth
- select a sub-tree or a set of species within the tree and view them graphically or as an alignment
- save a plain text representation of the tree
There is 1 interaction for this family. 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 PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Thiolase_C domain has been found. There are 158 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
Loading structure mapping...