Summary: Beta-ketoacyl synthase, C-terminal domain

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Wikipedia: Beta-ketoacyl-ACP synthase
Pfam
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Beta-ketoacyl-ACP synthase

3-oxoacyl-ACP synthase, mitochondrial
Identifiers
Symbol	OXSM
Entrez	54995
HUGO	26063
OMIM	610324
RefSeq	NM_017897
UniProt	Q9NWU1
Other data
EC number	2.3.1.41
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

Identifiers

Symbol

ketoacyl-synt

Pfam clan

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe
PDBsum	structure summary

Beta-ketoacyl synthase, C-terminal domain

arabidopsis thaliana mitochondrial beta-ketoacyl acp synthase hexanoic acid complex

Identifiers

Symbol

Ketoacyl-synt_C

Pfam clan

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe
PDBsum	structure summary

In molecular biology, Beta-ketoacyl-ACP synthase EC 2.3.1.41, is an enzyme involved in fatty acid synthesis. It results in the formation of acetoacetyl ACP.

It is the enzyme that catalyses the condensation of malonyl-ACP with the growing fatty acid chain.^[1] 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,^[2] 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^[3]

[edit] See also

Beta-Ketoacyl ACP reductase

[edit] External links

MeSH beta+Ketoacyl+ACP+Synthase

[edit] References

^ 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. 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. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1170466.

This article incorporates text from the public domain Pfam and InterPro IPR014030

This article incorporates text from the public domain Pfam and InterPro IPR014031

This transferase article is a stub. You can help Wikipedia by expanding it.

Transferases: acyltransferases (EC 2.3)

2.3.1: other than amino-acyl groups

palmitoyltransferases: Carnitine O-palmitoyltransferase (CPT1, CPT2)

Serine C-palmitoyltransferase (SPTLC1, SPTLC2)

other: Acyltransferase like 2

2.3.2: Aminoacyltransferases

2.3.3: converted into alkyl on transfer

B
enzm
- 1.1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 10
- 11
- 13
- 14
- 15-18
2.1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
2.7.10
2.7.11-12
3.1
- 2
- 3
- 4
- 5
- 6
- 7
3.1.3.48
3.4.21
- 22
- 23
- 24
4.1
- 2
- 3
- 4
- 5
- 6
5.1
- 2
- 3
- 4
- 99
6.1-3
- 4
- 5-6

Metabolism: lipid metabolism / fatty acid metabolism · triglyceride and fatty acid enzymes

Synthesis

Malonyl-CoA synthesis	ATP citrate lyase · Acetyl-CoA carboxylase

Fatty acid synthesis/ Fatty acid synthase	Beta-ketoacyl-ACP synthase · Β-Ketoacyl ACP reductase · 3-Hydroxyacyl ACP dehydrase · Enoyl ACP reductase

Fatty acid desaturases	Stearoyl-CoA_desaturase-1

Triacyl glycerol	Glycerol-3-phosphate dehydrogenase · Thiokinase

Degradation

Acyl transport

Carnitine palmitoyltransferase I · Carnitine-acylcarnitine translocase · Carnitine palmitoyltransferase II

Beta oxidation

General	Acyl CoA dehydrogenase (ACADL, ACADM, ACADS, ACADVL, ACADSB) · Enoyl-CoA hydratase MTP: HADH · HADHA · HADHB Acetyl-CoA C-acyltransferase

Unsaturated	Enoyl CoA isomerase · 2,4 Dienoyl-CoA reductase

Odd chain	Propionyl-CoA carboxylase

Other	Hydroxyacyl-Coenzyme A dehydrogenase

To acetyl-CoA

Malonyl-CoA decarboxylase

Aldehydes

Long-chain-aldehyde dehydrogenase

M: MET

mt, k, c/g/r/p/y/i, f/h/s/l/o/e, a/u, n, m

k, cgrp/y/i, f/h/s/l/o/e, au, n, m, epon

m(A16/C10),i(k, c/g/r/p/y/i, f/h/s/o/e, a/u, n, m)

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Beta-ketoacyl synthase, C-terminal domain

The structure of beta-ketoacyl synthase is similar to that of the thiolase family (PF00108) and also chalcone synthase. The active site of beta-ketoacyl synthase is located between the N and C-terminal domains.

Literature references

Huang W, Jia J, Edwards P, Dehesh K, Schneider G, Lindqvist Y; , EMBO J 1998;17:1183-1191.: Crystal structure of beta-ketoacyl-acyl carrier protein synthase II from E.coli reveals the molecular architecture of condensing enzymes. PUBMED:9482715

Clan

This family is a member of clan Thiolase (CL0046), which has a total of 13 members.

External database links

PANDIT:	PF02801
PROSITE:	PDOC00529
Pseudofam:	PF02801
SCOP:	1kas
SYSTERS:	Ketoacyl-synt_C

This tab holds annotation information from the InterPro database.

InterPro entry IPR014031

Beta-ketoacyl-ACP synthase EC (KAS) [PUBMED:3076376] is the enzyme that catalyzes 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 catalyzes 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 [PUBMED:2209605], 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.

This entry represents the C-terminal domain of beta-ketoacyl-ACP synthases. The active site is contained in a cleft betweeen N- and C-terminal domains, with residues from both domains contributing to substrate binding and catalysis [PUBMED:11152607].

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan Thiolase (CL0046), which contains the following 13 members:

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 ketoacyl-synt Ketoacyl-synt_2 Ketoacyl-synt_C SpoVAD Thiolase_C Thiolase_N

Alignments

There are various ways to view or download the sequence alignments that we store. You can use a sequence viewer to look at either the seed or full alignment for the family, or you can look at a plain text version of the sequence in a variety of different formats. More...

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Alignment:	Seed (166) Full (18000) NCBI (17176) Metagenomics (3918)
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Alignment:	Seed (166) Full (18000)
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The main seed and full alignments are generated using sequences from the UniProt sequence database. However, we also generate alignments using sequences from the NCBI sequence database and the "metaseq" metagenomics dataset.

You can view alignments from these two additional datasets using the form above, or you can download alignments of NCBI or metagenomics sequences, as gzip-compressed files.

Pfam alignments:	Seed (166) Full (18000) NCBI (17176) Metagenomics (3918)
Full length sequences	Full-sequences (18000)

External links

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Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation

Seed source:

Dotter

Previous IDs:

ketoacyl-synt_C;

Type:

Domain

Author:

Sonnhammer ELL, Griffiths-Jones SR

Number in seed:

166

Number in full:

18000

Average length of the domain:

107.10 aa

Average identity of full alignment:

36 %

Average coverage of the sequence by the domain:

6.53 %

HMM information

HMM build commands:

build method: hmmbuild -o /dev/null HMM SEED

search method: hmmsearch -Z 15929002 -E 1000 --cpu 4 HMM pfamseq

Model details:

Parameter	Sequence	Domain
Gathering cut-off	20.7	20.7
Trusted cut-off	20.7	20.7
Noise cut-off	20.6	20.6

Model length:

119

Family (HMM) version:

17

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download the raw HMM for this family

Species distribution

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Archea	Eukaryota
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Viroids	Unclassified sequence

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Interactions

There are 2 interactions for this family. More...

ketoacyl-synt Ketoacyl-synt_C

Structures

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 Ketoacyl-synt_C domain has been found. There are 65 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.

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Family: Ketoacyl-synt_C (PF02801)

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Summary: Beta-ketoacyl synthase, C-terminal domain

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Beta-ketoacyl-ACP synthase

[edit] See also

[edit] External links

[edit] References

Beta-ketoacyl synthase, C-terminal domain

Literature references

Clan

External database links

InterPro entry IPR014031

Domain organisation

Pfam Clan

Alignments

Viewing

Downloading

View options

Formatting options

Download options

External links

HMM logo

Trees

Curation and family details

Curation

HMM information

Species distribution

Sunburst controls

Weight segments by...

Change the size of the sunburst

Colour assignments

How the sunburst is generated

Colouring and labels

Anomalies in the taxonomy tree

Missing taxonomic levels

Unmapped species names

Sub-species

Too many species/sequences

Tree controls

Annotation

Download tree

Selected sequences

Species trees

Interactive tree

Interactions

Structures