Information on EC 1.14.19.26 - acyl-[acyl-carrier-protein] 6-desaturase

Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
Specify your search results
Select one or more organisms in this record:
Show additional data
Do not include text mining results
Include (text mining) results (more...)
Include results (AMENDA + additional results, but less precise; more...)

The enzyme appears in viruses and cellular organisms

EC NUMBER
COMMENTARY hide
1.14.19.26
-
RECOMMENDED NAME
GeneOntology No.
acyl-[acyl-carrier-protein] 6-desaturase
-
REACTION
REACTION DIAGRAM
COMMENTARY hide
ORGANISM
UNIPROT
LITERATURE
palmitoyl-[acyl-carrier protein] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = (6Z)-hexadec-6-enoyl-[acyl-carrier protein] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
show the reaction diagram
-
-
-
-
PATHWAY
BRENDA Link
KEGG Link
MetaCyc Link
sapienate biosynthesis
-
-
SYSTEMATIC NAME
IUBMB Comments
palmitoyl-[acyl-carrier protein],reduced ferredoxin:oxygen oxidoreductase (6,7 cis-dehydrogenating)
The enzyme, characterized from the endosperm of the plant Thunbergia alata (black-eyed Susan vine), introduces a cis double bond at carbon 6 of several saturated acyl-[acp]s. It is most active with palmitoyl-[acp] (16:0), but can also act on myristoyl-[acp] (14:0) and stearoyl-[acp] (18:0). The position of the double bond is determined by its distance from the carboxyl end of the fatty acid.
ORGANISM
COMMENTARY hide
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
-
UniProt
Manually annotated by BRENDA team
-
-
-
Manually annotated by BRENDA team
SUBSTRATE
PRODUCT                       
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
alpha-linolenic acid + ferrocytochrome b5 + O2 + H+
stearidonic acid + ferricytochrome b5 + H2O
show the reaction diagram
-
-
-
?
myristoyl-[acyl-carrier protein] + 2 reduced ferredoxin [iron-sulfur] cluster+ O2 + 2 H+
(Z)-tetradec-6-enoyl-[acyl-carrier protein] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
show the reaction diagram
-
-
-
-
?
oleic acid + ferrocytochrome b5 + O2 + H+
?
show the reaction diagram
-
-
-
?
palmitoleic acid + ferrocytochrome b5 + O2 + H+
?
show the reaction diagram
-
-
-
?
palmitoyl-[acyl-carrier protein] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+
(Z)-hexadec-6-enoyl-[acyl-carrier protein] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
show the reaction diagram
stearoyl-[acyl-carrier protein] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+
(Z)-octadec-6-enoyl-[acyl-carrier protein] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
show the reaction diagram
-
-
-
-
?
additional information
?
-
the fatty acids 16:3DELTA7,10,13, 20:2DELTA8,11, 20:3DELTA8,11,14 and 20:4DELTA5,8,11,14 do not serve as substrates
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
alpha-linolenic acid + ferrocytochrome b5 + O2 + H+
stearidonic acid + ferricytochrome b5 + H2O
show the reaction diagram
A7UFH0
-
-
-
?
palmitoyl-[acyl-carrier protein] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+
(Z)-hexadec-6-enoyl-[acyl-carrier protein] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
show the reaction diagram
COFACTOR
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
cytochrome b5
-
-
Ferredoxin
-
-
-
INHIBITORS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
H2O2
-
loss of most of the desaturase activity
KCN
-
1 mM, loss of most of the desaturase activity
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
additional information
palmitoyl-[acyl-carrier protein]
-
Km-values determined for the wild-type enzyme and mutant A188G/Y189F are in the range of 0.2 to 0.6 mM with both 16:0- and 18:0-[acyl-carrier protein], suggesting that, at least in the case of these enzymes, changes in the substrate binding properties can be discounted as an underlying cause of differences in activities
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
7.5
-
assay at
SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
SOURCE
LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY hide
GeneOntology No.
LITERATURE
SOURCE
Purification/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
Cloned/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
expressed in Saccharomyces cerevisiae strain InvSc1
expression in Escherichia coli
-
expression of wild-type and mutant enzymes in Escherichia coli
-
EXPRESSION
ORGANISM
UNIPROT
LITERATURE
dexamethasone at a dose of 1 mg/rat produces a significant decrease in microsomal DELTA6 desaturation activity 12 h after the injection
-
ENGINEERING
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
A181T/A188G/Y189F/S205N/L206T/G207A
-
the mutation yields an enzyme that functions primarily as a DELTA9-18:0-[acyl-carrier protein] desaturase. This enzyme displays only DELTA9 desaturase activity with 18:0-[acyl-carrier protein] and is nearly 4-fold more active with this substrate than with 16:0-[acyl-carrier protein]. Like mutant A181TyA200F, this enzyme retains DELTA6 desaturase activity with 16:0-[acyl-carrier protein]
A181T/A200F
-
the mutation gives rise to an enzyme that catalyzed primarily the DELTA9 desaturation of 18:0-[acyl-carrier protein], but functions as a DELTA6 desaturase with 16:0-[acyl-carrier protein]
A181T/A200F/S205N/L206T/G207A
-
replacement of specific amino acid residues in a DELTA6-palmitoyl (16:0)-[acyl-carrier protein] desaturase with their equivalents from a DELTA9-stearoyl (18:0)-[acyl-carrier protein] desaturase. The A181T/A200F/S205N/L206T/G207A mutant enzyme is functions principally as a DELTA9-18:0-[acyl-carrier protein] desaturase
A188G/Y189F
-
mutant with broadened fatty acid chain-length specificity
additional information
-
replacement of specific amino acid residues in a DELTA6-palmitoyl (16:0)-[acyl-carrier protein] desaturase with their equivalents from a DELTA9-stearoyl (18:0)-[acyl-carrier protein] desaturase, mutant enzymes are identified that have altered fatty acid chain-length specificities or that can insert double bonds into either the DELTA6 or DELTA9 positions of 16:0- and 18:0-[acyl-carrier protein]