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Information on EC 5.3.3.13 - polyenoic fatty acid isomerase
for references in articles please use BRENDA:EC5.3.3.13
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EC Tree 5 Isomerases
5.3 Intramolecular oxidoreductases
5.3.3 Transposing C=C bonds
5.3.3.13 polyenoic fatty acid isomerase
IUBMB Comments
The enzyme from the red alga Ptilota filicina catalyses the isomerization of skip dienes (methylene-interrupted double bonds) in a broad range of fatty acids and fatty-acid analogues, such as arachidonate and γ-linolenate, to yield a conjugated triene.
The expected taxonomic range for this enzyme is: Bacteria, Eukaryota
- 5.3.3.13
- acnes
-
propionibacterium
-
linoleic
- filicina
-
isomerization
-
arachidonic
-
triene
- chromophore
-
olefin
- lipase
Reaction Schemes
showSynonyms
polyenoic fatty acid isomerase, polyunsaturated fatty acid isomerase, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
eicosapentaenoate cis-DELTA5,8,11,14,17-eicosapentaenoate cis-DELTA5-trans-DELTA7,9-cis-D14,17 isomerase
-
-
-
-
PFI
-
-
-
-
polyunsaturated fatty acid double bond isomerase
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
(5Z,8Z,11Z,14Z,17Z)-icosapentaenoate = (5Z,7E,9E,14Z,17Z)-icosapentaenoate
-
-
-
-
(5Z,8Z,11Z,14Z,17Z)-icosapentaenoate = (5Z,7E,9E,14Z,17Z)-icosapentaenoate
mechansim of hydrogen transfers in the isomerization reaction including a diene intermediate
-
(5Z,8Z,11Z,14Z,17Z)-icosapentaenoate = (5Z,7E,9E,14Z,17Z)-icosapentaenoate
regio- and stereochemistry of the isomerization reaction, mechanism
-
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
isomerization
isomerization
-
-
-
-
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SYSTEMATIC NAME
IUBMB Comments
(5Z,8Z,11Z,14Z,17Z)-icosapentaenoate DELTA8,11-DELTA7,9-isomerase (trans-double-bond-forming)
The enzyme from the red alga Ptilota filicina catalyses the isomerization of skip dienes (methylene-interrupted double bonds) in a broad range of fatty acids and fatty-acid analogues, such as arachidonate and gamma-linolenate, to yield a conjugated triene.
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CAS REGISTRY NUMBER
COMMENTARY
159002-84-3
-
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
(4Z,7Z,10Z,13Z,16Z,19Z)-docosahexenoate
(4Z,7Z,9E,11E,16Z,19Z)-docosahexenoate
-
Substrates: excellent substrate
Products: -
Products: -
?
(5Z,8Z,11Z,14Z)-eicosatetraenoate
?
Substrates: arachidonic acid, conversion to the conjugated triene
Products: -
Products: -
?
(5Z,8Z,11Z,14Z)-eicosatetraenoyl methyl ester
(5Z,7E,9E,14Z,17Z)-eicosapentaenoyl methyl ester
-
Substrates: methyl ester of arachidonate
Products: -
Products: -
?
(5Z,8Z,11Z,14Z)-eicosatetraenoyl-N-ethanolamide
(5Z,7E,9E,14Z)-eicosatetraenoyl-N-ethanolamide
(5Z,8Z,11Z,14Z,17Z)-eicosa-5,8,11,14,17-pentaenoic acid
(5Z,7Z,9Z,14Z,17Z)-eicosa-5,7,9,14,17-pentaenoic acid
-
Substrates: -
Products: -
Products: -
?
(7Z,10Z,13Z,16Z)-docosatetraenoate
?
-
Substrates: adrenic acid
Products: -
Products: -
?
(8Z,11Z,14Z)-eicosatrienoate
?
-
Substrates: dihomo-gamma-linolenic acid, formation of two products: a conjugated triene and a conjugated diene
Products: -
Products: -
?
linoleic acid methyl ester
(10E,12Z)-octadeca-10,12-dienoic acid methyl ester
-
Substrates: -
Products: -
Products: -
?
linoleoyl-CoA
(10Z,12Z)-octadeca-10,12-dienoyl-CoA
-
Substrates: -
Products: -
Products: -
?
polyunstaurated fatty acid
?
-
Substrates: PFI catalyzes the formation of conjugated trienes from a variety of polyunsaturated fatty acid precursors, regio- and stereochemistry, enzyme may recognize the protonated from of the substrate
Products: -
Products: -
?
(5Z,8Z,11Z,14Z)-eicosatetraenoate
(5Z,7E,9E,14Z)-eicosatetraenoate
-
Substrates: arachidonic acid
Products: -
Products: -
?
(5Z,8Z,11Z,14Z)-eicosatetraenoate
(5Z,7E,9E,14Z)-eicosatetraenoate
-
Substrates: arachidonate, next best substrate after (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate, the C11 olefinic position becomes protonated by a solvent-derived proton, mechanism
Products: -
Products: -
?
(5Z,8Z,11Z,14Z)-eicosatetraenoyl-N-ethanolamide
(5Z,7E,9E,14Z)-eicosatetraenoyl-N-ethanolamide
-
Substrates: anandamide
Products: termed CTA, i.e. conjugated triene anandamide, cannabimimetic substance
Products: termed CTA, i.e. conjugated triene anandamide, cannabimimetic substance
?
(5Z,8Z,11Z,14Z)-eicosatetraenoyl-N-ethanolamide
(5Z,7E,9E,14Z)-eicosatetraenoyl-N-ethanolamide
-
Substrates: anandamide
Products: conjugated triene anandamide, cannabimimetic substance
Products: conjugated triene anandamide, cannabimimetic substance
?
(5Z,8Z,11Z,14Z)-eicosatetraenoyl-N-ethanolamide
(5Z,7E,9E,14Z)-eicosatetraenoyl-N-ethanolamide
-
Substrates: anandamide
Products: -
Products: -
?
(5Z,8Z,11Z,14Z)-eicosatetraenoyl-N-ethanolamide
(5Z,7E,9E,14Z)-eicosatetraenoyl-N-ethanolamide
-
Substrates: arachidonoylethanolamide
Products: -
Products: -
?
(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate
(5Z,7E,9E,14Z,17Z)-eicosapentaenoate
-
Substrates: likely the native substrate, biosynthesis of conjugated triene-containing fatty acids
Products: -
Products: -
?
(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate
(5Z,7E,9E,14Z,17Z)-eicosapentaenoate
Substrates: the preferred substrates are highly unsaturated free fatty acids such as eicosapentaenoic acid
Products: -
Products: -
?
(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate
(5Z,7E,9E,14Z,17Z)-eicosapentaenoate
-
Substrates: -
Products: -
Products: -
?
(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate
(5Z,7E,9E,14Z,17Z)-eicosapentaenoate
-
Substrates: best substrate, likely the native substrate, mechanism
Products: -
Products: -
?
(6Z,9Z,12Z)-octadecatrienoate
(6Z,8E,10E)-octadecatrienoate
-
Substrates: gamma-linolenic acid
Products: -
Products: -
?
(6Z,9Z,12Z)-octadecatrienoate
(6Z,8E,10E)-octadecatrienoate
-
Substrates: gamma-linolenate, PFI intramolecularly transfers the bis-allylic pro-S hydrogen from the C11 position to the C13 position, the bis-allylic pro-R hydrogen at C8 in gamma-linolenate is lost to the solvent
Products: -
Products: -
?
(9Z,12Z,15Z)-octadecatrienoate
?
-
Substrates: alpha-linolenic acid
Products: -
Products: -
?
(9Z,12Z,15Z)-octadecatrienoate
?
-
Substrates: alpha-linolenate, one-fifth as fast as gamma-linolenate
Products: -
Products: -
?
polyenoic fatty acid
?
-
Substrates: PFI is capable of isomerizing the methylene interrupted olefins of a wide range of polyenoic fatty acids into a conjugated triene functionality
Products: -
Products: -
?
polyenoic fatty acid
?
Substrates: PFI catalyzes the isomerization of a wide range of substrates containing three or more methylene interrupted olefins into a Z,E,E conjugated triene functionality
Products: -
Products: -
?
additional information
?
-
Substrates: PFI may be part of a stress tolerance mechanism
Products: -
Products: -
?
additional information
?
-
-
Substrates: PFI may be part of a stress tolerance mechanism
Products: -
Products: -
?
additional information
?
-
-
Substrates: substrate binding site, PFI preferentially orients the substrate in the catalytic site with respect to the methyl terminus and likely reacts, preferentially, with the protonated form of the substrate, not: linoleic acid
Products: -
Products: -
?
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate
(5Z,7E,9E,14Z,17Z)-eicosapentaenoate
-
Substrates: likely the native substrate, biosynthesis of conjugated triene-containing fatty acids
Products: -
Products: -
?
additional information
?
-
Substrates: PFI may be part of a stress tolerance mechanism
Products: -
Products: -
?
additional information
?
-
-
Substrates: PFI may be part of a stress tolerance mechanism
Products: -
Products: -
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
flavin
bound to PFI, cDNA contains a flavin-binding motif near the mature N-terminus
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
-
not inhibited by EDTA, o-phenanthroline, acetylsalicylic acid, baicalein, dipyridamole, eicosatetraynoic acid, esculetin, indomethacin, naproxen, NDGA or SKF-525A
-
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
additional information
-
study of the effect of the pH on kinetic parameters with several substrates
-
additional information
additional information
-
(11S-2H) linoleic acid, 0.00408, wild-type PAI
-
additional information
additional information
-
[11,11-2H2] linoleic acid, 0.00228, wild-type PAI
-
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
11.6
(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate
-
assuming one catalytic site per enzyme molecule
41
(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate
-
pH 7.2, assuming one catalytic site per enzyme molecule
additional information
additional information
-
(11S-2H) linoleic acid, 3.51, wild-type PAI
-
additional information
additional information
-
[11,11-2H2] linoleic acid, 0.83, wild-type PAI
-
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
4 - 8
-
there is a 30% increase in rate of product formation from pH 8 to 6.5, from pH 6.5 to 4.5 the apparent velocity increases 2.4fold, below pH 4 the activity slowly decreases
additional information
-
pH-dependence profile of PFI, catalytically active over a wide pH-range with (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate as substrate
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
22
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pI VALUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
4.9
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
Highest Expressing Human Cell Lines
Cell Line LinksPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). PFI_PTIFI
500
0
55960
Swiss-Prot
other Location (Reliability: 2)
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
53600
2 * 61000, SDS-PAGE, 2 * 55900, sequence calculation including the signal peptide, 2 * 53600, sequence calculation without the signal peptide
55900
2 * 61000, SDS-PAGE, 2 * 55900, sequence calculation including the signal peptide, 2 * 53600, sequence calculation without the signal peptide
61000
61000
2 * 61000, SDS-PAGE, 2 * 55900, sequence calculation including the signal peptide, 2 * 53600, sequence calculation without the signal peptide
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
homodimer
2 * 61000, SDS-PAGE, 2 * 55900, sequence calculation including the signal peptide, 2 * 53600, sequence calculation without the signal peptide
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POSTTRANSLATIONAL MODIFICATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
proteolytic modification
translation of a preprotein containing a signal peptide of 21 amino acids that is removed during maturation
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PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH STABILITY
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
-20C, purified PFI, months, stable
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Wise, M.L.; Hamberg, M.; Gerwick, W.H.
Biosynthesis of conjugated fatty acids by a novel isomerase from the red marine alga Ptilota filicina
Biochemistry
33
15223-15232
1994
Ptilota filicina
brenda
Wise, M.L.; Soderstrom, K.; Murray, T.F.; Gerwick, W.H.
Synthesis and cannabinoid receptor binding activity of conjugated triene anandamide, a novel eicosanoid
Experientia
52
88-92
1996
Ptilota filicina
brenda
Wise, M.L.; Rossi, J.; Gerwick, W.H.
Binding site characterization of polyenoic fatty-acid isomerase from the marine alga Ptilota filicina
Biochemistry
36
2985-2992
1997
Ptilota filicina
brenda
Gerwick, W.H.; Wise, M.L.; Soderstrom, K.; Murray, T.F.
Biosynthesis and cannabinoid receptor affinity of the novel eicosanoid, conjugated triene anandamide
Adv. Exp. Med. Biol.
407
329-334
1997
Ptilota filicina
brenda
Zheng, W.; Wise, M.L.; Wyrick, A.; Metz, J.G.; Yuan, L.; Gerwick, W.H.
Polyenoic fatty acid isomerase from the marine alga Ptilota filicina: protein characterization and functional expression of the cloned cDNA
Arch. Biochem. Biophys.
401
11-20
2002
Ptilota filicina (Q8W257), Ptilota filicina
brenda
Liavonchanka, A.; Feussner, I.
Biochemistry of PUFA double bond isomerases producing conjugated linoleic acid
ChemBioChem
9
1867-1872
2008
Ptilota filicina
brenda
Liavonchanka, A.; Rudolph, M.G.; Tittmann, K.; Hamberg, M.; Feussner, I.
On the mechanism of a polyunsaturated fatty acid double bond isomerase from Propionibacterium acnes
J. Biol. Chem.
284
8005-8012
2009
Cutibacterium acnes
brenda
EXTERNAL LINKS (specific for EC-Number 5.3.3.13)
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