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Reach

N-octadecanoylsphing-4-enine

362,296 routes · scope human · up to 3 steps · built 5 October 2026 · Reactions · API

Inferred

Every route here is a hypothesis drawn from reference reactions (Rhea and Human-GEM), not a finding. Currency species such as water, ATP and NAD(H) never form a step. Evidence key

265 compounds within 3 steps: 4 in 1, 57 in 2, 204 in 3

Does it reach a compound?

Two steps

cholesteryl octadecanoateReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. octadecanoyl-CoA + cholesterol = cholesteryl octadecanoate + CoA
Catalysed by GBA1, SOAT1
cholesteryl (5Z,8Z,11Z,14Z)-eicosatetraenoateReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. (5Z,8Z,11Z,14Z)-eicosatetraenoyl-CoA + cholesterol = cholesteryl (5Z,8Z,11Z,14Z)-eicosatetraenoate + CoA
Catalysed by GBA1, SOAT2, SOAT1One of 2 routes
sphinga-4E,14Z-dienineReach from here →
1. N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
2. sphing-4-enine + 2 Fe(II)-[cytochrome b5] + O2 + 2 H(+) = sphinga-4E,14Z-dienine + 2 Fe(III)-[cytochrome b5] + 2 H2O
Catalysed by ASAH1, ACER2, ASAH2, FADS3
cholesteryl (9Z)-hexadecenoateReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. (9Z)-hexadecenoyl-CoA + cholesterol = cholesteryl (9Z)-hexadecenoate + CoA
Catalysed by GBA1, SOAT1
(9Z,12Z,15Z-octadecatrienoyl)-cholesterolReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. (9Z,12Z,15Z)-octadecatrienoyl-CoA + cholesterol = (9Z,12Z,15Z-octadecatrienoyl)-cholesterol + CoA
Catalysed by GBA1, SOAT2One of 2 routes
cholesteryl (8Z,11Z,14Z)-eicosatrienoateReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. 1-hexadecanoyl-2-(8Z,11Z,14Z-eicosatrienoyl)-sn-glycero-3-phosphocholine + cholesterol = cholesteryl (8Z,11Z,14Z)-eicosatrienoate + 1-hexadecanoyl-sn-glycero-3-phosphocholine
Catalysed by GBA1, LCAT
(5Z,8Z,11Z,14Z,17Z-eicosapentaenoyl)-cholesterolReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoyl-CoA + cholesterol = (5Z,8Z,11Z,14Z,17Z-eicosapentaenoyl)-cholesterol + CoA
Catalysed by GBA1, SOAT2One of 2 routes
4beta-hydroxycholesterolReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. cholesterol + reduced [NADPH--hemoprotein reductase] + O2 = 4beta-hydroxycholesterol + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
Catalysed by GBA1, CYP3A4
cholesteryl (5Z,8Z,11Z)-eicosatrienoateReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. 1-hexadecanoyl-2-(5Z,8Z,11Z-eicosatrienoyl)-sn-glycero-3-phosphocholine + cholesterol = cholesteryl (5Z,8Z,11Z)-eicosatrienoate + 1-hexadecanoyl-sn-glycero-3-phosphocholine
Catalysed by GBA1, LCAT
(6Z,9Z,12Z-octadecatrienoyl)-cholesterolReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. 1-hexadecanoyl-2-(6Z,9Z,12Z-octadecatrienoyl)-sn-glycero-3-phosphocholine + cholesterol = (6Z,9Z,12Z-octadecatrienoyl)-cholesterol + 1-hexadecanoyl-sn-glycero-3-phosphocholine
Catalysed by GBA1, LCAT
cholesteryl (11Z)-octadecenoateReach from here →
1. beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
2. (11Z)-octadecenoyl-CoA + cholesterol = cholesteryl (11Z)-octadecenoate + CoA
Catalysed by GBA1, SOAT1

Three steps

CHEBI:1146900Reach from here →
Catalysed by ASAH1, ACER2, ASAH2, SLC27A2 and 11 morecytosolOne of 11 routes
(20R,22R)-20,22-dihydroxycholesterolReach from here →

Page 2 of 6

Catalysed by GBA1, CYP11A1

CHEBI:12947Reach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
sphing-4-enine + a fatty acyl-CoA = an N-acylsphing-4-enine + CoA + H(+)
UDP-alpha-D-galactose:N-acylsphingosine D-galactosyltransferase

Catalysed by ASAH1, ACER2, ASAH2, CERS1 and 6 morecytosolOne of 5 routes

CHEBI:1307929Reach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + (9Z)-octadecenoyl-CoA = cholesteryl (9Z-octadecenoate) + CoA
Steryl-ester acylhydrolase

Catalysed by GBA1, SOAT2, SOAT1, CEL and 1 morelysosomeOne of 18 routes

pregnenolone sulfateReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
6 reduced [adrenodoxin] + cholesterol + 3 O2 + 6 H(+) = 4-methylpentanal + pregnenolone + 6 oxidized [adrenodoxin] + 4 H2O
3'-phosphoadenylyl-sulfate:pregnenolone sulfotransferase

Catalysed by GBA1, CYP11A1, SULT2B1cytosolOne of 4 routes

N-octadecanoylglycineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
long-chain-fatty-acid-CoA ligase (stearate)
octadecanoyl-CoA + glycine = N-octadecanoylglycine + CoA + H(+)

Catalysed by ASAH1, ACER2, ASAH2, SLC27A2 and 7 morecytosol

(24S)-hydroxycholesterol 24-sulfateReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + reduced [NADPH--hemoprotein reductase] + O2 = (24S)-hydroxycholesterol + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
(24S)-hydroxycholesterol + 3'-phosphoadenylyl sulfate = (24S)-hydroxycholesterol 24-sulfate + adenosine 3',5'-bisphosphate + H(+)

Catalysed by GBA1, CYP46A1, SULT2A1

(24S)-hydroxycholesterol 3-sulfateReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + reduced [NADPH--hemoprotein reductase] + O2 = (24S)-hydroxycholesterol + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
(24S)-hydroxycholesterol + 3'-phosphoadenylyl sulfate = (24S)-hydroxycholesterol 3-sulfate + adenosine 3',5'-bisphosphate + H(+)

Catalysed by GBA1, CYP46A1, SULT2B1, SULT1E1 and 1 more

beta-D-glucosyl-N-(9Z-octadecenoyl)-sphing-4E-enineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
N-(9Z-octadecenoyl)-sphing-4-enine + H2O = sphing-4-enine + (9Z)-octadecenoate
beta-D-glucosyl-N-(9Z-octadecenoyl)-sphing-4E-enine + cholesterol = N-(9Z-octadecenoyl)-sphing-4-enine + cholesteryl 3-beta-D-glucoside

Catalysed by ASAH1, ACER2, ASAH2, ACER1 and 3 moreOne of 2 routes

an N-acyl-sphinga-4E,14Z-dienineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
sphing-4-enine + a fatty acyl-CoA = an N-acylsphing-4-enine + CoA + H(+)
an N-acylsphing-4-enine + 2 Fe(II)-[cytochrome b5] + O2 + 2 H(+) = an N-acyl-sphinga-4E,14Z-dienine + 2 Fe(III)-[cytochrome b5] + 2 H2O

Catalysed by ASAH1, ACER2, ASAH2, CERS1 and 6 more

2-(9Z-octadecenoyl)-sn-glycero-3-phospho-(1'-sn-glycerol)Reach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine + sphing-4-enine = 1-O-hexadecyl-sn-glycero-3-phosphocholine + N-(acetyl)-sphing-4-enine + H(+)
1-octadecanoyl-2-(9Z-octadecenoyl)-sn-glycero-3-phospho-(1'-sn-glycerol) + N-(acetyl)-sphing-4-enine = 2-(9Z-octadecenoyl)-sn-glycero-3-phospho-(1'-sn-glycerol) + 1-octadecanoyl-N-(acetyl)-sphing-4-enine

Catalysed by ASAH1, ACER2, ASAH2, PAFAH2 and 1 more

sn-glycero-3-phosphoethanolamineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine + sphing-4-enine = 1-O-hexadecyl-sn-glycero-3-phosphocholine + N-(acetyl)-sphing-4-enine + H(+)
1-O-hexadecyl-sn-glycero-3-phosphocholine + 1-hexadecanoyl-sn-glycero-3-phosphoethanolamine = 1-O-hexadecyl-2-hexadecanoyl-sn-glycero-3-phosphocholine + sn-glycero-3-phosphoethanolamine

Catalysed by ASAH1, ACER2, ASAH2, PAFAH2 and 1 moreOne of 2 routes

an N-octadecanoyl-sphingoid baseReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
long-chain-fatty-acid-CoA ligase (stearate)
a sphingoid base + octadecanoyl-CoA = an N-octadecanoyl-sphingoid base + CoA + H(+)

Catalysed by ASAH1, ACER2, ASAH2, SLC27A2 and 7 morecytosol

2-nonadioyl-sn-glycero-3-phosphocholineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine + sphing-4-enine = 1-O-hexadecyl-sn-glycero-3-phosphocholine + N-(acetyl)-sphing-4-enine + H(+)
1-hexadecanoyl-2-nonadioyl-sn-glycero-3-phosphocholine + N-(acetyl)-sphing-4-enine = 2-nonadioyl-sn-glycero-3-phosphocholine + 1-hexadecanoyl-N-(acetyl)-sphing-4-enine

Catalysed by ASAH1, ACER2, ASAH2, PAFAH2 and 1 more

N-hexadecanoyl-sphinga-4E,14Z-dienineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
sphing-4-enine + 2 Fe(II)-[cytochrome b5] + O2 + 2 H(+) = sphinga-4E,14Z-dienine + 2 Fe(III)-[cytochrome b5] + 2 H2O
sphinga-4E,14Z-dienine + hexadecanoyl-CoA = N-hexadecanoyl-sphinga-4E,14Z-dienine + CoA + H(+)

Catalysed by ASAH1, ACER2, ASAH2, FADS3 and 2 more

(7Z)-octadecenoyl-CoAReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
long-chain-fatty-acid-CoA ligase (stearate)
stearoyl-CoA 9-desaturase (stearoyl-CoA)

Catalysed by ASAH1, ACER2, ASAH2, SLC27A2 and 8 morecytosol

cholineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine + sphing-4-enine = 1-O-hexadecyl-sn-glycero-3-phosphocholine + N-(acetyl)-sphing-4-enine + H(+)
1-O-hexadecyl-sn-glycero-3-phosphocholine + H2O = 1-O-hexadecyl-sn-glycero-3-phosphate + choline + H(+)

Catalysed by ASAH1, ACER2, ASAH2, PAFAH2 and 3 moreOne of 2 routes

palmitoyl-CoAReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
long-chain-fatty-acid-CoA ligase (stearate)
Beta Oxidation of Long Chain Fatty Acid

Catalysed by ASAH1, ACER2, ASAH2, SLC27A2 and 10 morecytosol, peroxisome

oleoyl-CoAReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
long-chain-fatty-acid-CoA ligase (stearate)
stearoyl-CoA desaturase (N-C18:0CoA -> N-C18:1CoA)

Catalysed by ASAH1, ACER2, ASAH2, SLC27A2 and 7 morecytosolOne of 3 routes

betaine aldehydeReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + AH2 + O2 = 25-hydroxycholesterol + A + H2O
choline + A = betaine aldehyde + AH2

Catalysed by GBA1, CH25H, CHDH

hexadecanoic acidReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
(10Z)-heptadecenoic acid formation
(10Z)-heptadecenoic acid formation

Catalysed by ASAH1, ACER2, ASAH2cytosol, extracellular spaceOne of 16 routes

beta-D-glucoseReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + H2O = N-octadecanoylsphing-4-enine + D-glucose
D-glucose 1-epimerase

Catalysed by GBA1, GBA3, GALMcytosol

CHEBI:16174Reach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + H2O = N-octadecanoylsphing-4-enine + D-glucose
dATP:D-glucose 6-phosphotransferase

Catalysed by GBA1, GBA3, HK1, HK2 and 2 morecytosol

sulfateReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + 3'-phosphoadenylyl sulfate = cholesterol sulfate + adenosine 3',5'-bisphosphate + H(+)
Cholesterol-sulfate sulfohydrolase

Catalysed by GBA1, SULT2B1, SULT1C2, STScytosolOne of 4 routes

D-glucono-1,5-lactoneReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + H2O = N-octadecanoylsphing-4-enine + D-glucose
D-glucose + NAD(+) = D-glucono-1,5-lactone + NADH + H(+)

Catalysed by GBA1, GBA3, H6PDOne of 2 routes

oxaloacetateReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + AH2 + O2 = 25-hydroxycholesterol + A + H2O
(R)-malate + A = oxaloacetate + AH2

Catalysed by GBA1, CH25H, D2HGDH

1-phosphatidyl-1D-myo-inositolReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol 4-phosphate)(out) + cholesterol(in) = a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol 4-phosphate)(in) + cholesterol(out)
ATP:1-Phosphatidyl-1D-myo-inositol 4-phosphotransferase

Catalysed by GBA1, OSBP, PTPRQ, INPPL1 and 11 moreinner side of the membrane, outer side of the membrane, cytosolOne of 2 routes

formaldehydeReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + AH2 + O2 = 25-hydroxycholesterol + A + H2O
N(6),N(6)-dimethyl-L-lysyl(4)-[histone H3] + 2 A + 2 H2O = L-lysyl(4)-[histone H3] + 2 formaldehyde + 2 AH2

Catalysed by GBA1, CH25H, KDM1A, KDM1BOne of 3 routes

sn-glycerol 3-phosphocholineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine + sphing-4-enine = 1-O-hexadecyl-sn-glycero-3-phosphocholine + N-(acetyl)-sphing-4-enine + H(+)
1-O-hexadecyl-sn-glycero-3-phosphocholine + 1-hexadecanoyl-sn-glycero-3-phosphocholine = 1-O-hexadecyl-2-hexadecanoyl-sn-glycero-3-phosphocholine + sn-glycerol 3-phosphocholine

Catalysed by ASAH1, ACER2, ASAH2, PAFAH2 and 1 moreOne of 7 routes

progesteroneReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
6 reduced [adrenodoxin] + cholesterol + 3 O2 + 6 H(+) = 4-methylpentanal + pregnenolone + 6 oxidized [adrenodoxin] + 4 H2O
Pregnenolone:NAD+ 3-oxidoreductase

Catalysed by GBA1, CYP11A1, HSD3B1, HSD3B2cytosolOne of 2 routes

N-octadecanoyl-heptadecasphing-4-enineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
long-chain-fatty-acid-CoA ligase (stearate)
heptadecasphing-4-enine + octadecanoyl-CoA = N-octadecanoyl-heptadecasphing-4-enine + CoA + H(+)

Catalysed by ASAH1, ACER2, ASAH2, SLC27A2 and 7 morecytosol

all-trans-retinolReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + AH2 + O2 = 25-hydroxycholesterol + A + H2O
all-trans-13,14-dihydroretinol + A = all-trans-retinol + AH2

Catalysed by GBA1, CH25H, RETSAT

linoleic acidReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
(10Z)-heptadecenoic acid formation
(10Z)-heptadecenoic acid formation

Catalysed by ASAH1, ACER2, ASAH2cytosol, extracellular spaceOne of 14 routes

AH2Reach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + AH2 + O2 = 25-hydroxycholesterol + A + H2O
A + NADH + H(+) = AH2 + NAD(+)

Catalysed by GBA1, CH25H, AIFM1, PYROXD1One of 19 routes

O-phosphoethanolamineReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
ATP:sphingosine 1-phosphotransferase
sphingosine-1-phosphate palmitaldehyde-lyase (phosphoethanolamine-forming)

Catalysed by ASAH1, ACER2, ASAH2, DBP and 3 morecytosolOne of 2 routes

L-cysteineReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
cholesterol + AH2 + O2 = 25-hydroxycholesterol + A + H2O
Mo-molybdopterin + L-cysteine + AH2 = thio-Mo-molybdopterin + L-alanine + A + H2O

Catalysed by GBA1, CH25H, MOCOS

(2E)-hexadecenalReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
ATP:sphingosine 1-phosphotransferase
sphingosine-1-phosphate palmitaldehyde-lyase (phosphoethanolamine-forming)

Catalysed by ASAH1, ACER2, ASAH2, DBP and 3 morecytosolOne of 2 routes

a sphingomyelinReach from here →

N-octadecanoylsphing-4-enine + H2O = sphing-4-enine + octadecanoate
sphing-4-enine + a fatty acyl-CoA = an N-acylsphing-4-enine + CoA + H(+)
ceramide:phosphatidylcholine cholinephosphotransferase

Catalysed by ASAH1, ACER2, ASAH2, CERS1 and 7 moreGolgi apparatusOne of 8 routes

lactoseReach from here →

beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + cholesterol = cholesteryl 3-beta-D-glucoside + N-octadecanoylsphing-4-enine
beta-D-glucosyl-(1<->1)-N-octadecanoylsphing-4-enine + H2O = N-octadecanoylsphing-4-enine + D-glucose
D-glucose + UDP-alpha-D-galactose = lactose + UDP + H(+)

Catalysed by GBA1, GBA3, B4GALT2, B4GALT1