D4FAD_DIALT
ID D4FAD_DIALT Reviewed; 445 AA.
AC Q6VPV2;
DT 11-NOV-2015, integrated into UniProtKB/Swiss-Prot.
DT 05-JUL-2004, sequence version 1.
DT 03-AUG-2022, entry version 67.
DE RecName: Full=Acyl-lipid (7-3)-desaturase {ECO:0000305};
DE EC=1.14.19.31 {ECO:0000305|PubMed:14572666};
DE AltName: Full=Acyl-lipid 4-desaturase {ECO:0000305};
DE AltName: Full=Delta-4 fatty acid desaturase {ECO:0000303|PubMed:14572666};
GN Name=Plesd1 {ECO:0000303|PubMed:14572666};
GN Synonyms=des1 {ECO:0000312|EMBL:AAQ98793.1};
OS Diacronema lutheri (Unicellular marine alga) (Monochrysis lutheri).
OC Eukaryota; Haptista; Haptophyta; Pavlovales; Pavlovaceae; Diacronema.
OX NCBI_TaxID=2081491;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, AND CATALYTIC ACTIVITY.
RC STRAIN=CCAP 931/1;
RX PubMed=14572666; DOI=10.1016/s0014-5793(03)01078-0;
RA Tonon T., Harvey D., Larson T.R., Graham I.A.;
RT "Identification of a very long chain polyunsaturated fatty acid Delta4-
RT desaturase from the microalga Pavlova lutheri.";
RL FEBS Lett. 553:440-444(2003).
CC -!- FUNCTION: Fatty acid desaturase that introduces a cis double bond at
CC the 4-position in 22-carbon polyunsaturated fatty acids that contain a
CC Delta(7) double bond, resulting in the production of delta-4
CC desaturated fatty acid docosahexanoic acid (DHA). Mediates desaturation
CC of 22:5n-3 and 22:4n-6 into 22:6n-3 and 22:5n-6 respectively.
CC {ECO:0000269|PubMed:14572666}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=a (7Z,10Z,13Z,16Z,19Z)-docosapentaenoyl-containing
CC glycerolipid + 2 Fe(II)-[cytochrome b5] + 2 H(+) + O2 = a
CC (4Z,7Z,10Z,13Z,16Z,19Z)-docosahexaenoyl-containing glycerolipid + 2
CC Fe(III)-[cytochrome b5] + 2 H2O; Xref=Rhea:RHEA:46252, Rhea:RHEA-
CC COMP:10438, Rhea:RHEA-COMP:10439, ChEBI:CHEBI:15377,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:29033,
CC ChEBI:CHEBI:29034, ChEBI:CHEBI:88266, ChEBI:CHEBI:88267;
CC EC=1.14.19.31; Evidence={ECO:0000305|PubMed:14572666};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=a (7Z,10Z,13Z,16Z)-docosatetraenoyl-containing glycerolipid +
CC 2 Fe(II)-[cytochrome b5] + 2 H(+) + O2 = a (4Z,7Z,10Z,13Z,16Z)-
CC docosapentaenoyl-containing glycerolipid + 2 Fe(III)-[cytochrome b5]
CC + 2 H2O; Xref=Rhea:RHEA:46256, Rhea:RHEA-COMP:10438, Rhea:RHEA-
CC COMP:10439, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379,
CC ChEBI:CHEBI:29033, ChEBI:CHEBI:29034, ChEBI:CHEBI:88264,
CC ChEBI:CHEBI:88265; EC=1.14.19.31;
CC Evidence={ECO:0000305|PubMed:14572666};
CC -!- COFACTOR:
CC Name=Fe(2+); Xref=ChEBI:CHEBI:29033;
CC Evidence={ECO:0000250|UniProtKB:O00767};
CC -!- SUBCELLULAR LOCATION: Membrane {ECO:0000255}; Multi-pass membrane
CC protein {ECO:0000255}.
CC -!- DOMAIN: The cytochrome b5 heme-binding domain acts as the direct
CC electron donor to the active site of the desaturase, and does not
CC require an external cytochrome. {ECO:0000305}.
CC -!- SIMILARITY: Belongs to the fatty acid desaturase type 1 family.
CC {ECO:0000305}.
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DR EMBL; AY332747; AAQ98793.1; -; mRNA.
DR AlphaFoldDB; Q6VPV2; -.
DR SMR; Q6VPV2; -.
DR BioCyc; MetaCyc:MON-16993; -.
DR BRENDA; 1.14.19.31; 7928.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR GO; GO:0016717; F:oxidoreductase activity, acting on paired donors, with oxidation of a pair of donors resulting in the reduction of molecular oxygen to two molecules of water; IDA:UniProtKB.
DR GO; GO:0042759; P:long-chain fatty acid biosynthetic process; IDA:UniProtKB.
DR GO; GO:0006636; P:unsaturated fatty acid biosynthetic process; IDA:UniProtKB.
DR Gene3D; 3.10.120.10; -; 1.
DR InterPro; IPR001199; Cyt_B5-like_heme/steroid-bd.
DR InterPro; IPR036400; Cyt_B5-like_heme/steroid_sf.
DR InterPro; IPR005804; FA_desaturase_dom.
DR InterPro; IPR012171; Fatty_acid_desaturase.
DR PANTHER; PTHR19353; PTHR19353; 1.
DR Pfam; PF00173; Cyt-b5; 1.
DR Pfam; PF00487; FA_desaturase; 1.
DR PIRSF; PIRSF015921; FA_sphinglp_des; 1.
DR SMART; SM01117; Cyt-b5; 1.
DR SUPFAM; SSF55856; SSF55856; 1.
DR PROSITE; PS50255; CYTOCHROME_B5_2; 1.
PE 1: Evidence at protein level;
KW Electron transport; Fatty acid biosynthesis; Fatty acid metabolism; Heme;
KW Iron; Lipid biosynthesis; Lipid metabolism; Membrane; Metal-binding;
KW Oxidoreductase; Transmembrane; Transmembrane helix; Transport.
FT CHAIN 1..445
FT /note="Acyl-lipid (7-3)-desaturase"
FT /id="PRO_0000434756"
FT TRANSMEM 126..146
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 148..168
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 247..267
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 283..303
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 312..332
FT /note="Helical"
FT /evidence="ECO:0000255"
FT DOMAIN 11..91
FT /note="Cytochrome b5 heme-binding"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00279"
FT MOTIF 170..174
FT /note="Histidine box-1"
FT /evidence="ECO:0000305"
FT MOTIF 205..210
FT /note="Histidine box-2"
FT /evidence="ECO:0000305"
FT MOTIF 380..384
FT /note="Histidine box-3"
FT /evidence="ECO:0000305"
FT BINDING 50
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00279"
FT BINDING 73
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00279"
SQ SEQUENCE 445 AA; 49062 MW; D7A11532FB4D4620 CRC64;
MPPSAASEGG VAELRAAEVA SYTRKAVDER PDLTIVGDAV YDAKAFRDEH PGGAHFVSLF
GGRDATEAFM EYHRRAWPKA RMSKFFVGSL DASEKPTQAD SAYLRLCAEV NALLPKGSGG
FAPPSYWLKA AALVVAAVSI EGYMLLRGKT LLLSVFLGLV FAWIGLNIQH DANHGALSRH
SVINYCLGYA QDWIGGNMVL WLQEHVVMHH LHTNDVDADP DQKAHGVLRL KPTDGWMPWH
ALQQLYILPG EAMYAFKLLF LDALELLAWR WEGEKISPLA RALFAPAVAC KLGFWARFVA
LPLWLQPTVH TALCICATVC TGSFYLAFFF FISHNFDGVG SVGPKGSLPR SATFVQRQVE
TSSNVGGYWL GVLNGGLNFQ IEHHLFPRLH HSYYAQIAPV VRTHIEKLGF KYRHFPTVGS
NLSSMLQHMG KMGTRPGAEK GGKAE
