Information on EC 2.3.1.135 - phosphatidylcholine-retinol O-acyltransferase

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The expected taxonomic range for this enzyme is: Eukaryota, Bacteria

EC NUMBER
COMMENTARY hide
2.3.1.135
-
RECOMMENDED NAME
GeneOntology No.
phosphatidylcholine-retinol O-acyltransferase
REACTION
REACTION DIAGRAM
COMMENTARY hide
ORGANISM
UNIPROT
LITERATURE
phosphatidylcholine + retinol-[cellular-retinol-binding-protein] = 2-acylglycerophosphocholine + retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
Acyl group transfer
-
-
-
-
PATHWAY
BRENDA Link
KEGG Link
MetaCyc Link
retinol biosynthesis
-
-
Retinol metabolism
-
-
the visual cycle I (vertebrates)
-
-
SYSTEMATIC NAME
IUBMB Comments
phosphatidylcholine:retinol---[cellular-retinol-binding-protein] O-acyltransferase
A key enzyme in retinoid metabolism, catalysing the transfer of an acyl group from the sn-1 position of phosphatidylcholine to retinol, forming retinyl esters which are then stored. Recognizes the substrate both in free form and when bound to cellular-retinol-binding-protein, but has higher affinity for the bound form. Can also esterify 11-cis-retinol.
CAS REGISTRY NUMBER
COMMENTARY hide
117444-03-8
-
ORGANISM
COMMENTARY hide
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
-
-
-
Manually annotated by BRENDA team
strain 129S2/Sv
-
-
Manually annotated by BRENDA team
gene Lrat
-
-
Manually annotated by BRENDA team
C57BL/6J mice
-
-
Manually annotated by BRENDA team
no activity in Gallus gallus
not found in glial cells
-
-
Manually annotated by BRENDA team
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
evolution
malfunction
metabolism
-
the key step of vitamin A metabolism is the esterification of all-trans retinol, catalyzed by lecithin/retinol acyltransferase, LRAT. Vitamin A metabolism in benign and malignant melanocytic skin cells with regard to expression, functional activity of LRAT, RPE65, and cRBP2 and their regulation, overview
physiological function
additional information
SUBSTRATE
PRODUCT                       
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
1-lauroyl-2-myristoylphosphatidylcholine + retinol-(cellular-retinol-binding-protein)type II
retinyl laurate-(cellular-retinol-binding-protein)type II + 2-myristoylphosphatidylcholine
show the reaction diagram
-
-
-
?
1-myristoyl-2-lauroylphosphatidylcholine + retinol-(cellular-retinol-binding-protein)type II
retinyl myristate-(cellular-retinol-binding-protein)type II + 2-lauroylphosphatidylcholine
show the reaction diagram
-
-
-
?
1-palmitoyl-2-acetyl-sn-glycerol-3-phosphorylcholine + retinol
retinyl palmitate + 2-acetyl-sn-glycerol-3-phosphorylcholine
show the reaction diagram
-
-
-
?
1-palmitoyl-2-decanoylphosphatidylcholine + retinol-(cellular-retinol-binding-protein)type II
retinyl palmitate-(cellular-retinol-binding-protein)type II + 2-decanoylphosphatidylcholine
show the reaction diagram
-
-
-
?
1-palmitoyl-2-linoleoyl-sn-glycerol-3-phosphorylcholine + retinol
retinyl palmitate + 2-linoleoyl-sn-glycerol-3-phosphorylcholine
show the reaction diagram
-
most effective substrate in stimulating palmitate transfer above control levels
-
?
1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphorylcholine + retinol
retinyl palmitate + 2-oleoyl-sn-glycerol-3-phosphorylcholine
show the reaction diagram
-
-
-
?
1-palmitoyl-2-stearoyl-sn-glycerol-3-phosphorylcholine + retinol
retinyl palmitate + 2-stearoyl-sn-glycerol-3-phosphorylcholine
show the reaction diagram
-
-
-
?
1-palmitoyl-sn-glycerol-3-phosphorylcholine + retinol
retinyl palmitate + glycerol-3-phosphorylcholine
show the reaction diagram
-
-
-
?
didecanoylphosphatidylcholine + all-trans-retinol
all-trans-retinyl decanoate + 2-decanoylglycerophosphocholine
show the reaction diagram
-
-
activity is about 10% of that with diheptanoylphosphatidylcholine
-
?
diheptanoylphosphatidylcholine + all-trans-retinol
all-trans-retinyl heptanoate + 2-heptanoylglycerophosphocholine
show the reaction diagram
-
-
-
-
?
dilauroylphosphatidylcholine + all-trans-retinol
all-trans-retinyl laurate + 2-lauroylglycerophosphocholine
show the reaction diagram
-
-
activity is about 4% of that with diheptanoylphosphatidylcholine
-
?
dilauroylphosphatidylcholine + retinol-(cellular retinol binding protein)type II
retinyl laurate-(cellular retinol binding protein)type II + 2-lauroyl-phosphatidylcholine
show the reaction diagram
-
-
-
?
dimyristoylphosphatidic acid + retinol-(cellular retinol binding protein) type II
retinyl myristate + myristoylphosphatidic acid
show the reaction diagram
-
little if any retinyl myristate obtained
-
?
dimyristoylphosphatidylcholine + all-trans-retinol
all-trans-retinyl myristate + 2-myristoylglycerophosphocholine
show the reaction diagram
-
activity is about 3% of that with diheptanoylphosphatidylcholine
-
-
?
dimyristoylphosphatidylcholine + retinol(cellular retinol binding protein)type II
retinyl myristate-(cellular retinol binding protein)type II + 2-myristoyl-phosphatidylcholine
show the reaction diagram
-
-
-
?
dimyristoylphosphatidylethanolamine + retinol-(cellular retinol binding protein) type II
retinyl myristate-(cellular retinol binding protein)type II + myristoyl-phosphatidylethanolamine
show the reaction diagram
-
little if any retinyl myristate obtained
-
?
dioctanoylphosphatidylcholine + all-trans-retinol
all-trans-retinyl octanoate + 2-octanoylglycerophosphocholine
show the reaction diagram
-
activity is less than 15% of that with diheptanoylphosphatidylcholine
-
-
?
dioleoylphosphatidylcholine + all-trans-retinol
all-trans-retinyl oleate + 2-oleoylglycerophosphocholine
show the reaction diagram
-
-
-
-
?
dipalmitoylphosphatidylcholine + all-trans-retinol
all-trans-retinyl palmitate + 2-palmitoylglycerophosphocholine
show the reaction diagram
lecithin + 11-cis-retinol-[cellular retinol-binding protein]
2-acylglycerophosphocholine + 11-cis-retinyl ester-[cellular retinol-binding protein]
show the reaction diagram
-
-
-
-
r
lecithin + all-trans-retinol-[cellular retinol-binding protein]
2-acylglycerophosphocholine + all-trans-retinyl ester-[cellular retinol-binding protein]
show the reaction diagram
-
-
-
-
r
lecithin + retinol-[cellular retinol-binding protein III]
2-acylglycerophosphocholine + retinyl ester-[cellular retinol-binding protein III]
show the reaction diagram
lecithin + retinol-[cellular retinol-binding protein]
2-acylglycerophosphocholine + retinyl ester-[cellular retinol-binding protein]
show the reaction diagram
palmitoyl-CoA + 11-cis-retinol-[cellular retinol-binding protein]
CoA + 11-cis-retinyl palmitate-[cellular retinol-binding protein]
show the reaction diagram
palmitoyl-CoA + all-trans-retinol-[cellular retinol-binding protein]
CoA + all-trans-retinyl palmitate-[cellular retinol-binding protein]
show the reaction diagram
phosphatidylcholine + 11-cis-retinol
11-cis-retinyl acyl ester + 2-acylglycerophosphocholine
show the reaction diagram
-
-
-
r
phosphatidylcholine + 11-cis-retinol
2-acylglycerophosphocholine + 11-cis-retinyl acyl ester
show the reaction diagram
phosphatidylcholine + 11-cis-retinol
2-acylglycerophosphocholine + 11-cis-retinyl palmitate
show the reaction diagram
-
low activity
-
-
?
phosphatidylcholine + 11-cis-retinol-[cellular-retinol-binding-protein]
2-acylglycerophosphocholine + 11-cis-retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
phosphatidylcholine + 11-cis-retinoll-[cellular-retinol-binding-protein]
2-acylglycerophosphocholine + 11-cis-retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
-
trans-esterification reaction is reversible, however in the presence of the isomerase, all-trans-retinyl esters are converted to 11-cis-retinol which is enzymatically oxidized to 11-cis-retinal, the chromophore of vision. Both all-trans-retinol and 11-cis-retinol are substrates for LRAT esterification, although all-transretinol is the preferred substrate.
-
-
r
phosphatidylcholine + all-trans-retinol
2-acylglycerophosphocholine + all-trans-retinyl acyl ester
show the reaction diagram
phosphatidylcholine + all-trans-retinol
2-acylglycerophosphocholine + all-trans-retinyl acylester
show the reaction diagram
phosphatidylcholine + all-trans-retinol
2-acylglycerophosphocholine + all-trans-retinyl ester
show the reaction diagram
phosphatidylcholine + all-trans-retinol
2-acylglycerophosphocholine + all-trans-retinyl palmitate
show the reaction diagram
-
-
-
-
?
phosphatidylcholine + all-trans-retinol
2-acylglycerophosphocholine + retinyl ester
show the reaction diagram
phosphatidylcholine + all-trans-retinol
all-trans-retinyl acyl esters + 2-acylglycerophosphocholine
show the reaction diagram
phosphatidylcholine + all-trans-retinol-(bovine serum albumin)
all-trans-retinyl acyl ester-(bovine serum albumin) + 2-acylglycerophosphocholine
show the reaction diagram
-
-
?
phosphatidylcholine + all-trans-retinol-[cellular-retinol-binding-protein]
2-acylglycerophosphocholine + all-trans-retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
phosphatidylcholine + all-trans-retinylamine
2-acylglycerophosphocholine + all-trans-retinyl acylamide
show the reaction diagram
-
-
-
-
?
phosphatidylcholine + all-trans-retinylamine
2-acylglycerophosphocholine + fatty acid-N-all-trans-retinyl amide
show the reaction diagram
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-
product identification
-
?
phosphatidylcholine + retinol-(cellular-retinol-binding protein) type II
2-acylglycerophosphocholine + retinyl ester-(cellular-retinol-binding-protein) type II
show the reaction diagram
phosphatidylcholine + retinol-(cellular-retinol-binding-protein)
2-acylglycerophosphocholine + retinyl ester-(cellular-retinol-binding-protein)
show the reaction diagram
phosphatidylcholine + retinol-[cellular-retinol-binding-protein]
2-acylglycerophosphocholine + retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
phosphatidylcholine + retinylamine
2-acylglycerophosphocholine + fatty acid N-retinylamide
show the reaction diagram
-
-
product identification
-
?
additional information
?
-
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
lecithin + 11-cis-retinol-[cellular retinol-binding protein]
2-acylglycerophosphocholine + 11-cis-retinyl ester-[cellular retinol-binding protein]
show the reaction diagram
-
-
-
-
r
lecithin + all-trans-retinol-[cellular retinol-binding protein]
2-acylglycerophosphocholine + all-trans-retinyl ester-[cellular retinol-binding protein]
show the reaction diagram
-
-
-
-
r
lecithin + retinol-[cellular retinol-binding protein III]
2-acylglycerophosphocholine + retinyl ester-[cellular retinol-binding protein III]
show the reaction diagram
lecithin + retinol-[cellular retinol-binding protein]
2-acylglycerophosphocholine + retinyl ester-[cellular retinol-binding protein]
show the reaction diagram
palmitoyl-CoA + 11-cis-retinol-[cellular retinol-binding protein]
CoA + 11-cis-retinyl palmitate-[cellular retinol-binding protein]
show the reaction diagram
-
esterification of 11-cis-retinol is four times greater than esterification of all-trans-retinol in Muller cells
-
-
?
palmitoyl-CoA + all-trans-retinol-[cellular retinol-binding protein]
CoA + all-trans-retinyl palmitate-[cellular retinol-binding protein]
show the reaction diagram
-
esterification of 11-cis-retinol is four times greater than esterification of all-trans-retinol in Muller cells
-
-
?
phosphatidylcholine + 11-cis-retinol
2-acylglycerophosphocholine + 11-cis-retinyl acyl ester
show the reaction diagram
-
essential for generation of the precursor for 11-cis-retinal, the visual chromophore in the eye
-
-
?
phosphatidylcholine + 11-cis-retinol-[cellular-retinol-binding-protein]
2-acylglycerophosphocholine + 11-cis-retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
-
trans-esterification reaction is reversible, however in the presence of the isomerase, all-trans-retinyl esters are converted to 11-cis-retinol which is enzymatically oxidized to 11-cis-retinal, the chromophore of vision. Both all-trans-retinol and 11-cis-retinol are substrates for LRAT esterification, although all-transretinol is the preferred substrate.
-
-
r
phosphatidylcholine + 11-cis-retinoll-[cellular-retinol-binding-protein]
2-acylglycerophosphocholine + 11-cis-retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
-
trans-esterification reaction is reversible, however in the presence of the isomerase, all-trans-retinyl esters are converted to 11-cis-retinol which is enzymatically oxidized to 11-cis-retinal, the chromophore of vision. Both all-trans-retinol and 11-cis-retinol are substrates for LRAT esterification, although all-transretinol is the preferred substrate.
-
-
r
phosphatidylcholine + all-trans-retinol
2-acylglycerophosphocholine + all-trans-retinyl acyl ester
show the reaction diagram
-
enzyme is involved in vitamin A storage and mobilization
-
-
r
phosphatidylcholine + all-trans-retinol
2-acylglycerophosphocholine + all-trans-retinyl ester
show the reaction diagram
-
LRAT catalyzes the transfer of an acyl group from the sn-1 position of phosphatidylcholine to all-trans-retinol, vitamin A
-
-
?
phosphatidylcholine + all-trans-retinol
2-acylglycerophosphocholine + retinyl ester
show the reaction diagram
-
LRAT catalyzes the transfer of an acyl group from the sn-1 position of phosphatidylcholine to all-trans-retinol, vitamin A
-
-
?
phosphatidylcholine + all-trans-retinol
all-trans-retinyl acyl esters + 2-acylglycerophosphocholine
show the reaction diagram
phosphatidylcholine + all-trans-retinol-[cellular-retinol-binding-protein]
2-acylglycerophosphocholine + all-trans-retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
phosphatidylcholine + all-trans-retinylamine
2-acylglycerophosphocholine + all-trans-retinyl acylamide
show the reaction diagram
-
-
-
-
?
phosphatidylcholine + retinol-[cellular-retinol-binding-protein]
2-acylglycerophosphocholine + retinyl-ester-[cellular-retinol-binding-protein]
show the reaction diagram
phosphatidylcholine + retinylamine
2-acylglycerophosphocholine + fatty acid N-retinylamide
show the reaction diagram
-
-
-
-
?
additional information
?
-
METALS and IONS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
INHIBITORS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
13-demethyl-13,14-dihydro-all-trans-retinyl trifluoroacetate
-
competitive with respect to dipalmitoylphosphocholine, uncompetitive with respect to all-trans-retinol; reversible inhibitor
all-trans-retinyl-alpha-bromoacetate
all-trans-retinylbromoacetate
-
-
Apo-cellular-retinol-binding protein
-
-
-
apo-CRBP-I
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i.e. apo-[cellular retinol-binding protein I], no inhibition by apo-CRBP-III
-
fenretinide
-
used clinically to presumably lower blood retinol-binding protein levels and thus decrease circulating retinol, targets the functional coupling of STRA6 and LRAT to increase cellular vitamin A uptake in peripheral tissues
N-Boc-L-biocytinyl-11-aminoundecan chloromethylketone
-
0.002 mM, 45% inhibition; irreversible inhibitor; time dependent inhibition
N-ethylmaleimide
p-chloromercuribenzoic acid
-
0.005 mM, complete inhibition of retinol-(cellular-retinol-binding-protein)type II esterification
palmitoyl-CoA
-
-
phenylmethylsulfonyl fluoride
retinyl bromoacetate
-
78% reduction of enzyme activity
retinylamine
additional information
-
ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
cellular retinol-binding protein
-
N-(4-hydroxyphenyl)-retinamide
-
necessary dose, 0.5 mg; restores normal level of LRAT activity in vitamin A depleted rats
retinoic acid
SDS
-
SDS is necessary for tLRAT extraction from cell lysates. tLRAT enzymatic activity drastically diminishes at SDS concentrations below 0.05% and remains unchanged when SDS concentration is increased from 0.05 to 1%. SDS is very important for tLRAT stability
Vitamin A
additional information
-
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
0.006
11-cis-retinol
-
reaction with phosphatidylcholine
0.0023 - 0.0113
11-cis-retinol-[cellular retinol-binding protein]
0.0001 - 0.055
all-trans-retinol
0.00033 - 0.0288
all-trans-retinol-[cellular retinol-binding protein]
0.00024
all-trans-retinol-[cellular-retinol-binding-protein]
-
pH and temperature not specified in the publication
-
0.00138
dipalmitoylphosphatidylcholine
-
reaction with all-trans-retinol
0.00044 - 0.00063
retinol
0.0002 - 0.001
retinol-(cellular-retinol-binding protein)
-
0.00024
retinol-(cellular-retinol-binding protein) type II
-
intestinal LRAT, reaction with phosphatidylcholine
-
0.0005
retinol-(cellular-retinol-binding-protein)
-
reaction with phosphatidylcholine
-
0.00032
retinol-cellular-retinol-binding protein type II
-
liver LRAT, reaction with phosphatidylcholine
-
additional information
additional information
-
TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
40.4
all-trans-retinol
Homo sapiens
-
pH not specified in the publication, 20°C
kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
730
all-trans-retinol
Homo sapiens
-
pH not specified in the publication, 20°C
847
SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
0.0000001
-
nonparenchymal cell fraction LRAT activity and hepatocyte cell fraction LRAT activity for vitamin A-deficient rats
0.0000012
-
hepatocyte cell fraction LRAT activity for vitamin A-deficient rats treated with retinoic acid
0.000003
-
hepatocyte fraction LRAT activity of vitamin A-sufficient rats
0.0000054
-
hepatocyte cell fraction LRAT activity for vitamin A-deficient rats treated with N-(4-hydroxyphenyl)-retinamide
0.0000132
-
nonparenchymal cell fraction LRAT activity for vitamin A-deficient rats treated with retinoic acid
0.00003
-
intestinal LRAT
0.0000309
-
nonparenchymal cell fraction LRAT activity for vitamin A-sufficient rats
0.000036
-
vitamin A-deficient rats treated orally with retinyl palmitate
0.0000401
-
vitamin A-deficient rats treated intraperitoneally with retinoic acid
0.0000415
-
vitamin A-deficient rats treated intraperitoneally with retinol
0.0000434
-
vitamin A-deficient rats treated orally with retinoic acid
0.0000553
-
nonparenchymal cell fraction LRAT activity for vitamin A-deficient rats treated with N-(4-hydroxyphenyl)-retinamide
0.00006
-
mammary gland LRAT
0.000094
-
testis LRAT
0.000145
-
liver LRAT
0.0021
-
liver LRAT activity in vitamin A-deficient rats
0.1
-
retinal pigment epithelial LRAT
0.166
-
11-cis-retinyl ester synthesis in presence of cellular retinol-binding protein
additional information
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
6
-
assay at
7.5 - 8
8
-
assay at
8.5
-
assay at
9
-
about
pH RANGE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
10
-
80% of maximum activity
additional information
-
pH profile of recombinant mutant enzymes and recombinant truncated wild-type
TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
20
-
assay at
20 - 25
-
-
TEMPERATURE RANGE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
35
-
15% of maximum activity
SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
SOURCE
mRNA expression
Manually annotated by BRENDA team
-
in the glomeruli of normal, neoplastic kidney sections
Manually annotated by BRENDA team
-
mRNA expression in adult stage
Manually annotated by BRENDA team
-
breast carcinoma cells have lower LRAT activity
Manually annotated by BRENDA team
-
neoplastic and adjacent, non-neoplastic glandular breast tissue specimens from human patients, expression analysis, reduced enzyme expression, LRAT protein progressively decreases with a reduction in the degree of tumor differentiation in invasive breast carcinomas, overview
Manually annotated by BRENDA team
-
skin, these cells have lower LRAT activity
Manually annotated by BRENDA team
-
LRAT acts together with Cyp26A1, one of the enzymes that catalyze the degradation of retinoic acid, and possibly with STRA6, the cell surface receptor for retinol-retinol-binding protein, in maintaining adequate levels of retinoids in embryonic and extraembryonic tissues
Manually annotated by BRENDA team
-
epidermal
Manually annotated by BRENDA team
-
diverse cell lines
Manually annotated by BRENDA team
-
primary cell culture
Manually annotated by BRENDA team
-
mRNA expression in adult stage
Manually annotated by BRENDA team
-
epithelial cells
Manually annotated by BRENDA team
-
-
Manually annotated by BRENDA team
additional information
LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY hide
GeneOntology No.
LITERATURE
SOURCE
-
before initiation of retinyl ester biosynthesis, LRAT distributes throughout the endoplasmic reticulum, and Crpb1 localizes with mitochondria associated membranes, surrounded by LRAT. Upon initiating retinyl ester biosynthesis in cells, Crpb1 remains with MAM, and both Crbp1 and MAM re-localize with LRAT. LRAT formed rings around the growing lipid droplets
Manually annotated by BRENDA team
-
LRATis a single membrane-spanning protein with an N-terminal domain that faces the cytoplasm, C-terminal luminal orientation, membrane topology, overview; LRAT is localized to the membrane of the LRAT is localized to the membrane of the endoplasmic reticulum. Single membrane-spanning protein with an N-terminal domain that faces the cytoplasm
Manually annotated by BRENDA team
-
upon initiating retinyl ester biosynthesis in cells, Crpb1 remains with MAM, and both Crbp1 and MAM re-localize with LRAT. LRAT formed rings around the growing lipid droplets. LRAT-containing rings colocalize with the lipid-droplet surface proteins, desnutrin/adipose triglyceride lipase and perilipin 2. Colocalization with lipid droplets requires the 38 N-terminal amino acid residues of LRAT, and specifically K36 and R38. Formation of rings around the growing lipid droplets does not require functional microtubules
-
Manually annotated by BRENDA team
additional information
-
subcellular localization study, overview
-
Manually annotated by BRENDA team
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
20000
-
1 * 25000, full-length wild-type enzyme, SDS-PAGE, 1 * 20000, recombinant truncated enzyme, SDS-PAGE; 2 * 25000, full-length wild-type enzyme, SDS-PAGE, 2 * 20000, recombinant truncated enzyme, SDS-PAGE
20900
-
x * 20900
40000
-
nonreducing PAGE, higher aggregation, up to pentamers, occurs in absence of denaturing agents
SUBUNITS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
dimer
-
2 * 25000, full-length wild-type enzyme, SDS-PAGE, 2 * 20000, recombinant truncated enzyme, SDS-PAGE
homodimer
-
2 × 25300, SDS-PAGE in presence of 2-mercaptoethanol; SDS-PAGE in absence of 2-mercaptoethanol
monomer
additional information
Crystallization/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
2.2 A crystal structure of HRAS-like tumor suppressor 3 /LRAT chimeric enzyme in a thioester catalytic intermediate state reveals a major structural rearrangement accompanied by 3D-domain swapping dimerization not observed in native HRASLS proteins. Structural changes affecting the active site environment contribute to slower hydrolysis of the catalytic intermediate supporting efficient acyl transfer
-
pH STABILITY
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
10.4
-
inactivation of recombinant truncated wild-type enzyme, reversible by dialysis against a buffer with pH 8.4
658075
TEMPERATURE STABILITY
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
37
-
half-life in absence of substrate: 17 min
GENERAL STABILITY
ORGANISM
UNIPROT
LITERATURE
all operation involving retinoids are performed at darkness, or under red light
buffers are bubbled with argon prior to use
-
dithiothreitol stabilizes
-
ORGANIC SOLVENT
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
Triton X-100
-
the high similarity between the secondary structure of tLRAT in the absence and the presence of Triton X-100 suggests that this detergent has no detectable effect on the structure of this protein
STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
-70°C, 100 mM Tris-HCl, pH 8.3, 0.4% Triton X-100, stable for several days
-
-70°C, 20 mM Tris-HCl pH 9, 2 mM dithiothreitol, 1 mM EDTA, 0.1% Triton X-100, 0.1 mg/ml dipalmitoylphosphatidylcholine, NaCl, stable for months
-
-80°C, 10 mM Tris acetate, pH 7, 1 mM dithiothreitol, microsomal fraction, stable for at least 6 months
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Purification/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
affinity labeling with all-trans-retinyl-alpha-bromoacetate, SDS electrophoresis, prior to affinity labelling, incubation with cholesterol chloroacetate to block nucleophilic reagents, or streptavidin column to remove endogenously biotinylated proteins enhance protein purification; affinity labeling with N-Boc-L-biocytinyl-11-aminoundecan chloromethylketone, precipitation and gel electrophoresis, prior to affinity labelling, incubation with cholesterol chloroacetate to block nucleophilic reagents, or streptavidin column to remove endogenously biotinylated proteins enhance protein purification; labeling with N-Boc-L-biocytinyl-11-aminoundecan chloromethylketone, affinity chromatography, avidin, prior to affinity chromatography or affinity labelling, incubation with cholesterol chloroacetate to block nucleophilic reagents, or streptavidin column to remove endogenously biotinylated proteins enhance protein purification
-
affinity labeling with all-trans-retinyl-alpha-bromoacetate, SDS electrophoresis, prior to affinity labelling, incubation with cholesterol chloroacetate to block nucleophilic reagents, or streptavidin column to remove endogenously biotinylated proteins enhance protein purification; affinity labeling with N-Boc-L-biocytinyl-11-aminoundecan chloromethylketone, precipitation and gel electrophoresis, prior to affinity labelling, incubation with cholesterol chloroacetate to block nucleophilic reagents, or streptavidin column to remove endogenously biotinylated proteins enhance protein purification; labeling with N-Boc-L-biocytinyl-11-aminoundecan chloromethylketone, affinity chromatography, avidin, prior to affinity chromatography or affinity labelling, incubation with cholesterol chloroacetate to block nucleophilic reagents, or streptavidin column to remove endogenously biotinylated proteins enhance protein purification; solubilization of membranes and centrifugation, chromatography on DEAE-column and Mono-Q column later on, quantitative information
-
enzyme transfected in HEK-293T cells partially purificated by solubilization and centrifugation
-
histidine-tagged truncated LRAT
-
native enzyme partially by membrane preparation
-
native enzyme partially by membrane preparation from retinal pigment epithelium
native enzyme partially by microsome preparation from eyes, recombinant enzyme partially from HEK-293T cells by membrane preparation
-
recombinant His-tagged LRAT by affinity chromatography
-
recombinant His-tagged truncated wild-type and mutant enzymes from Escherichia coli strain BL21(DE3) by nickel affinity chromatography in presence of 1% SDS
-
recombinant truncated enzyme from Escherichia coli in presence of 1% SDS, by nickel affinity chromatography to homogeneity
-
recombinant truncated tLRAT and its S175R mutant
-
SDS is necessary for tLRAT extraction from cell lysates. tLRAT enzymatic activity drastically diminishes at SDS concentrations below 0.05% and remains unchanged when SDS concentration is increased from 0.05 to 1%. SDS is very important for tLRAT stability. Detergents such as 0.2% Triton X-100, 0.7% CHAPSO,and 1.2 mM n-dodecyl-beta-D-maltoside and sodium are not effective
-
solubilization of membranes and centrifugation, chromatography: mono Q column and Green 5-agarose column
-
solubilization, centrifugation and dialysis
-
Cloned/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
; expression of wild-type and/or mutant enzymes inducibly in HEK-293 cells, transiently in COS-7 cells, and in Escherichia coli strain BL21(DE3) cells
-
DNA sequence determination and analysis of the full length gene including the 3'- and 5'-ends, genetic organization analysis, at least 2 splicing variants, the second of which lacks a 103 nt polynucleotide in the 5'-UTR of the full length transcript
-
expression in HEK-293 cells; expression in HEK-293T cells
-
expression in HEK-293T cells
expression of a truncated enzyme form lacking the transmembrane N- and C-termini in Escherichia coli as His-tagged protein, which is insoluble in absence of detergents
-
expression of His-tagged truncated wild-type enzyme and His-tagged mutant enzymes in Escherichia coli strain BL21(DE3)
-
gene lrat is localized on chromosome 4 at locus 4q31.2
-
gene Lrat, vector cloning for construction of knockout mutants
-
inducible expression of LRAT in HEK-293S cells
LRAT, quantitative real-time RT-PCR expression analysis in melanoma cell lines
-
recombinant expression of His-tagged LRAT
-
recombinant expression of the truncated tLRAT and its S175R mutant
-
stable expression in HEK-293T cells
stable expression of GFP-tagged LRAT in CHO cells and of GFP-tagged LRAT in COS7 cells
-
stable expression of LRAT in HEK-293T cell membranes
-
EXPRESSION
ORGANISM
UNIPROT
LITERATURE
expression of LRAT and RPE65 can be modulated by retinoids
-
interleukin-1 can potently downregulate mRNA and protein levels of LRAT and act as injury signal resulting in mobilization of retinyl esters in primary rat hepatic stellate cells. Secreted factors from Kupffer cells are able to suppress LRAT expression in hepatic stellate cells, which is neutralized by interleukin-1 receptor antagonist. The regulation is likely at transcriptional level. Interleukin-1 fails to downregulate recombinant LRAT protein expressed in the cells by adenovirus, while transcription of endogenous LRAT is promptly decreased. Interleukin-1 is a key mediator to down-regulate LRAT in liver injury
-
ENGINEERING
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
K104A
-
site-directed mutagenesis, reduced activity compared to the truncated wild-type enzyme
K133A
-
site-directed mutagenesis, increased activity compared to the truncated wild-type enzyme
K133A/K134A
-
site-directed mutagenesis, slightly increased activity compared to the truncated wild-type enzyme
K134A
-
site-directed mutagenesis, increased activity compared to the truncated wild-type enzyme
K147A
-
site-directed mutagenesis, reduced activity compared to the truncated wild-type enzyme
K180A
-
site-directed mutagenesis, nearly inactive mutant
K180R
-
site-directed mutagenesis, reduced activity compared to the truncated wild-type enzyme
K186A
-
site-directed mutagenesis, nearly inactive mutant
K186R
-
site-directed mutagenesis, reduced activity compared to the truncated wild-type enzyme
K90A
-
site-directed mutagenesis, highly reduced activity compared to the truncated wild-type enzyme
K95A
-
site-directed mutagenesis, highly reduced activity compared to the truncated wild-type enzyme
Y118F
-
site-directed mutagenesis, activity similar to the truncated wild-type enzyme
Y154F
-
site-directed mutagenesis, inactive mutant
Y167F
-
site-directed mutagenesis, activity similar to the truncated wild-type enzyme
Y64F
-
site-directed mutagenesis, highly increased activity compared to the truncated wild-type enzyme
D128N
-
site-directed mutagenesis, construction of an N-glycosylation site for enzyme membrane localization and orientation studies, overview
I42N
-
site-directed mutagenesis, construction of an N-glycosylation site for enzyme membrane localization and orientation studies, overview
additional information
APPLICATION
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
analysis
-
ARPE-19 cell system is appropriate for studying the visual cycle enzymes
diagnostics
medicine