{PDOC00150}
{PS00166; ENOYL_COA_HYDRATASE}
{BEGIN}
*******************************************
* Enoyl-CoA hydratase/isomerase signature *
*******************************************

Enoyl-CoA hydratase  (EC 4.2.1.17)   (ECH)  [1]  and D3,D2-enoyl-CoA isomerase
(EC 5.3.3.8) (ECI) [2] are two enzymes involved in fatty acid metabolism.  ECH
catalyzes the hydratation of 2-trans-enoyl-CoA into 3-hydroxyacyl-CoA  and ECI
shifts the 3- double  bond  of  the  intermediates  of  unsaturated fatty acid
oxidation to the 2-trans position.

Most eukaryotic cells have two fatty-acid  beta-oxidation systems, one located
in mitochondria and the other in peroxisomes. In mitochondria, ECH and ECI are
separate yet structurally related monofunctional enzymes.  Peroxisomes contain
a trifunctional  enzyme [3] consisting of an N-terminal domain that bears both
ECH and  ECI  activity, and a C-terminal domain responsible for 3-hydroxyacyl-
CoA dehydrogenase (HCDH) activity.

In Escherichia coli (gene fadB) and Pseudomonas fragi (gene faoA), ECH and ECI
are also  part  of  a multifunctional  enzyme which contains both a HCDH and a
3-hydroxybutyryl-CoA epimerase domain [4].

A number  of other proteins  have been found to be evolutionary related to the
ECH/ECI enzymes or domains:

 - 3-hydroxbutyryl-coa  dehydratase  (EC  4.2.1.55)  (crotonase),  a bacterial
   enzyme involved in the butyrate/butanol-producing pathway.
 - Naphthoate  synthase  (EC  4.1.3.36)  (DHNA  synthase)  (gene  menB) [5], a
   bacterial enzyme  involved in the biosynthesis of menaquinone (vitamin K2).
   DHNA synthase converts O-succinyl-benzoyl-CoA (OSB-CoA) to 1,4-dihydroxy-2-
   naphthoic acid (DHNA).
 - 4-chlorobenzoate dehalogenase (EC 3.8.1.6) [6], a  Pseudomonas enzyme which
   catalyzes the conversion of 4-chlorobenzoate-CoA to 4-hydroxybenzoate-CoA.
 - A Rhodobacter capsulatus protein of unknown function (ORF257) [7].
 - Bacillus subtilis putative polyketide biosynthesis proteins pksH and pksI.
 - Escherichia coli carnitine racemase (gene caiD) [8].
 - Escherichia coli hypothetical protein ygfG.
 - Yeast hypothetical protein YDR036c.

As a signature pattern for these enzymes, we selected  a conserved region rich
in glycine and hydrophobic residues.

-Consensus pattern: [LIVM]-[STAG]-x-[LIVM]-[DENQRHSTA]-G-x(3)-[AG](3)-x(4)-
                    [LIVMST]-x-[CSTA]-[DQHP]-[LIVMFYA]
-Sequences known to belong to this class detected by the pattern: ALL.
-Other sequence(s) detected in Swiss-Prot: 5.

-Expert(s) to contact by email:
           Hofmann K.; kay.hofmann@memorec.com

-Last update: December 2004 / Pattern and text revised.

[ 1] Minami-Ishii N., Taketani S., Osumi T., Hashimoto T.
     Eur. J. Biochem. 185:73-78(1989).
[ 2] Mueller-Newen G., Stoffel W.
     Biol. Chem. Hoppe-Seyler 372:613-624(1991).
[ 3] Palosaari P.M., Hiltunen J.K.
     "Peroxisomal bifunctional protein from rat liver is a trifunctional
     enzyme possessing 2-enoyl-CoA hydratase, 3-hydroxyacyl-CoA
     dehydrogenase, and delta 3, delta 2-enoyl-CoA isomerase activities."
     J. Biol. Chem. 265:2446-2449(1990).
     PubMed=2303409
[ 4] Nakahigashi K., Inokuchi H.
     "Nucleotide sequence of the fadA and fadB genes from Escherichia
     coli."
     Nucleic Acids Res. 18:4937-4937(1990).
     PubMed=2204034
[ 5] Driscoll J.R., Taber H.W.
     "Sequence organization and regulation of the Bacillus subtilis menBE
     operon."
     J. Bacteriol. 174:5063-5071(1992).
     PubMed=1629163
[ 6] Babbitt P.C., Kenyon G.L., Martin B.M., Charest H., Slyvestre M.,
     Scholten J.D., Chang K.-H., Liang P.-H., Dunaway-Mariano D.
     "Ancestry of the 4-chlorobenzoate dehalogenase: analysis of amino acid
     sequence identities among families of acyl:adenyl ligases, enoyl-CoA
     hydratases/isomerases, and acyl-CoA thioesterases."
     Biochemistry 31:5594-5604(1992).
     PubMed=1351742
[ 7] Beckman D.L., Kranz R.G.
     "A bacterial homolog to the mitochondrial enoyl-CoA hydratase."
     Gene 107:171-172(1991).
     PubMed=1743516
[ 8] Eichler K., Bourgis F., Buchet A., Kleber H.-P., Mandrand-Berthelot M.-A.
     "Molecular characterization of the cai operon necessary for carnitine
     metabolism in Escherichia coli."
     Mol. Microbiol. 13:775-786(1994).
     PubMed=7815937

--------------------------------------------------------------------------------
PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and
distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives
(CC BY-NC-ND 4.0) License, see https://prosite.expasy.org/prosite_license.html
--------------------------------------------------------------------------------

{END}