Translations:Metabolism/87/en

Major metabolic pathways in metro-style map. Click any text (name of pathway or metabolites) to link to the corresponding article.
Single lines: pathways common to most lifeforms. Double lines: pathways not in humans (occurs in e.g. plants, fungi, prokaryotes).

Orange nodes: carbohydrate metabolism.

Violet nodes: photosynthesis.

Red nodes: cellular respiration.

Pink nodes: cell signaling.

Blue nodes: amino acid metabolism.

Grey nodes: vitamin and cofactor metabolism.

Brown nodes: nucleotide and protein metabolism.

Green nodes: lipid metabolism.

Metabolism, catabolism, anabolism

General

Energy
metabolism

Aerobic respiration	Glycolysis → Pyruvate decarboxylation → Citric acid cycle → Oxidative phosphorylation (electron transport chain + ATP synthase)
Anaerobic respiration	Electron acceptors other than oxygen
Fermentation	Glycolysis → Substrate-level phosphorylation ABE Ethanol Lactic acid

Specific
paths

Protein metabolism

Protein synthesis
Catabolism (protein→peptide→amino acid)

Amino acid	Amino acid synthesis Amino acid degradation (amino acid→pyruvate, acetyl CoA, or TCA intermediate) Urea cycle
Nucleotide metabolism	Purine metabolism Nucleotide salvage Pyrimidine metabolism Purine nucleotide cycle

Carbohydrate metabolism
(carbohydrate catabolism
and anabolism)

Human

Glycolysis ⇄ Gluconeogenesis
Glycogenolysis ⇄ Glycogenesis
Pentose phosphate pathway Fructolysis Polyol pathway Galactolysis Leloir pathway
Glycosylation N-linked O-linked

Nonhuman

Photosynthesis Anoxygenic photosynthesis Chemosynthesis Carbon fixation DeLey-Doudoroff pathway Entner-Doudoroff pathway
Xylose metabolism Radiotrophism

Lipid metabolism
(lipolysis, lipogenesis)

Fatty acid metabolism	Fatty acid degradation (Beta oxidation) Fatty acid synthesis
Other	Steroid metabolism Sphingolipid metabolism Eicosanoid metabolism Ketosis Reverse cholesterol transport

Other

Metabolism: carbohydrate metabolism: glycolysis/gluconeogenesis enzymes

Glycolysis

Gluconeogenesis only

to oxaloacetate:	Pyruvate carboxylase Phosphoenolpyruvate carboxykinase
from lactate (Cori cycle):	Lactate dehydrogenase
from alanine (Alanine cycle):	Alanine transaminase
from glycerol:	Glycerol kinase Glycerol dehydrogenase

Regulatory

v t e Metabolism: carbohydrate metabolism fructose and galactose enzymes
Fructose / Fructolysis	Hepatic fructokinase Aldolase B Triokinase
Sorbitol	Sorbitol dehydrogenase Aldose reductase
Galactose / Galactolysis	Galactokinase Galactose-1-phosphate uridylyltransferase/UDP-glucose 4-epimerase Aldose reductase
Lactose	Lactose synthase Lactase
Mannose	Mannose phosphate isomerase

glycosaminoglycan anabolism

Heparan sulfate: EXT1; EXT2

Chondroitin sulfate: PAPSS1; PAPSS2

glycosaminoglycan catabolism

Hunter, Hurler	Iduronate-2-sulfatase Iduronidase
Sanfilippo, Sly	Heparan sulfamidase N-acetyltransferase Alpha-N-acetylglucosaminidase Glucuronidase N-acetylglucosamine-6-sulfatase
Morquio/Maroteaux-Lamy	Arylsulfatase B Galactosamine-6 sulfatase Beta-galactosidase (GLB1)

v t e Metabolism: carbohydrate metabolism · glycoprotein enzymes
Anabolism	Dolichol kinase GCS1 Oligosaccharyltransferase
Catabolism	Neuraminidase Beta-galactosidase Hexosaminidase mannosidase alpha-Mannosidase beta-mannosidase Aspartylglucosaminidase Fucosidase NAGA
Transport	SLC17A5
M6P tagging	N-acetylglucosamine-1-phosphate transferase

Metabolism, lipid metabolism, glycolipid enzymes

Sphingolipid

To glycosphingolipid	Glycosyltransferase Sulfotransferase
To ceramide	From ganglioside Beta-galactosidase Hexosaminidase A Neuraminidase Glucocerebrosidase From globoside Hexosaminidase B Alpha-galactosidase Beta-galactosidase Glucocerebrosidase From sphingomyelin Sphingomyelin phosphodiesterase Sphingomyelin phosphodiesterase 1 From sulfatide Arylsulfatase A Galactosylceramidase
To sphingosine	Ceramidase ACER1 ACER2 ACER3 ASAH1 ASAH2 ASAH2B ASAH2C
Other	Sphingosine kinase

NCL

Ceramide synthesis

v t e Metabolism: lipid metabolism – eicosanoid metabolism enzymes
Precursor	Phospholipase A2 Phospholipase C Diacylglycerol lipase
Prostanoids	Cyclooxygenase PTGS1 PTGS2 PGD2 synthase PGE synthase Prostaglandin-E2 9-reductase PGI2 synthase TXA synthase
Leukotrienes	5-Lipoxygenase activating protein/Arachidonate 5-lipoxygenase LTA4 hydrolase (B4 synthesis) LTC4 synthase Gamma-glutamyl transpeptidase LTD4 hydrolase
Ungrouped	HPGD

Metabolism: lipid metabolism / fatty acid metabolism, triglyceride and fatty acid enzymes

Synthesis

Malonyl-CoA synthesis	ATP citrate lyase Acetyl-CoA carboxylase
Fatty acid synthesis/ Fatty acid synthase	Beta-ketoacyl-ACP synthase Β-Ketoacyl ACP reductase 3-Hydroxyacyl ACP dehydrase Enoyl ACP reductase
Fatty acid desaturases	Stearoyl-CoA desaturase-1
Triacyl glycerol	Glycerol-3-phosphate dehydrogenase Thiokinase

Degradation

Acyl transport

Beta oxidation

General	Acyl CoA dehydrogenase (ACADL ACADM ACADS ACADVL ACADSB) Enoyl-CoA hydratase MTP: HADH HADHA HADHB Acetyl-CoA C-acyltransferase
Unsaturated	Enoyl CoA isomerase 2,4 Dienoyl-CoA reductase
Odd chain	Propionyl-CoA carboxylase
Other	Hydroxyacyl-Coenzyme A dehydrogenase

To acetyl-CoA

Malonyl-CoA decarboxylase

Aldehydes

Long-chain-aldehyde dehydrogenase

Metabolism: amino acid metabolism - urea cycle enzymes

Main cycle

mitochondrial matrix:	Carbamoyl phosphate synthetase I Ornithine transcarbamylase
cytosol:	Argininosuccinate synthetase Argininosuccinate lyase Arginase

Regulatory/transport

Enzymes involved in neurotransmission

monoamine

histidine → histamine

anabolism:	Histidine decarboxylase
catabolism:	Histamine N-methyltransferase Diamine oxidase

tyrosine→dopamine→epinephrine

anabolism:	Tyrosine hydroxylase Aromatic L-amino acid decarboxylase Dopamine beta-hydroxylase Phenylethanolamine N-methyltransferase
catabolism:	Catechol-O-methyl transferase Monoamine oxidase A B

glutamate→GABA

anabolism:	Glutamate decarboxylase
catabolism:	4-aminobutyrate transaminase

tryptophan→serotonin→melatonin

arginine→NO

Nitric oxide synthase (NOS1, NOS2, NOS3)

choline→Acetylcholine

anabolism:	Choline acetyltransferase
catabolism:	Cholinesterase (Acetylcholinesterase, Butyrylcholinesterase)

Enzymes involved in the metabolism of heme and porphyrin

Porphyrin biosynthesis

early mitochondrial:	Aminolevulinic acid synthase ALAS1 ALAS2
cytosolic:	Porphobilinogen synthase Porphobilinogen deaminase Uroporphyrinogen III synthase Uroporphyrinogen III decarboxylase
late mitochondrial:	Coproporphyrinogen III oxidase Protoporphyrinogen oxidase Ferrochelatase

Heme degradation
to bile

spleen:	Heme oxygenase Biliverdin reductase
liver:	glucuronosyltransferase UGT1A1

Metabolism of vitamins, coenzymes, and cofactors

Fat soluble vitamins

Vitamin A	Retinol binding protein
Vitamin E	Alpha-tocopherol transfer protein
Vitamin D	liver (Sterol 27-hydroxylase or CYP27A1) renal (25-Hydroxyvitamin D₃ 1-alpha-hydroxylase or CYP27B1) degradation (1,25-Dihydroxyvitamin D₃ 24-hydroxylase or CYP24A1)
Vitamin K	Vitamin K epoxide reductase

Water soluble vitamins

Thiamine (B₁)

Thiamine diphosphokinase

Niacin (B₃)

Pantothenic acid (B₅)

Pantothenate kinase

Folic acid (B₉)

Dihydropteroate synthase Dihydrofolate reductase Serine hydroxymethyltransferase
Methylenetetrahydrofolate reductase

Vitamin B₁₂

Vitamin C

L-gulonolactone oxidase

Riboflavin (B₂)

Riboflavin kinase

Nonvitamin cofactors

Tetrahydrobiopterin

GTP cyclohydrolase I 6-pyruvoyltetrahydropterin synthase Sepiapterin reductase
PCBD1 PTS QDPR

Molybdopterin

Metabolism: Protein metabolism, synthesis and catabolism enzymes

Essential amino acids are in Capitals

K→acetyl-CoA

LYSINE→	Saccharopine dehydrogenase Glutaryl-CoA dehydrogenase
LEUCINE→	3-Hydroxybutyryl-CoA dehydrogenase Branched-chain amino acid aminotransferase Branched-chain alpha-keto acid dehydrogenase complex Enoyl-CoA hydratase HMG-CoA lyase HMG-CoA reductase Isovaleryl coenzyme A dehydrogenase α-Ketoisocaproate dioxygenase Leucine 2,3-aminomutase Methylcrotonyl-CoA carboxylase Methylglutaconyl-CoA hydratase (See Template:Leucine metabolism in humans – this diagram does not include the pathway for β-leucine synthesis via leucine 2,3-aminomutase)
TRYPTOPHAN→	Indoleamine 2,3-dioxygenase/Tryptophan 2,3-dioxygenase Arylformamidase Kynureninase 3-hydroxyanthranilate oxidase Aminocarboxymuconate-semialdehyde decarboxylase Aminomuconate-semialdehyde dehydrogenase
PHENYLALANINE→tyrosine→	(see below)

G→pyruvate
→citrate

glycine→serine→	Serine hydroxymethyltransferase Serine dehydratase glycine→creatine: Guanidinoacetate N-methyltransferase Creatine kinase
alanine→	Alanine transaminase
cysteine→	D-cysteine desulfhydrase
threonine→	L-threonine dehydrogenase

G→glutamate→
α-ketoglutarate

HISTIDINE→	Histidine ammonia-lyase Urocanate hydratase Formiminotransferase cyclodeaminase
proline→	Proline oxidase Pyrroline-5-carboxylate reductase 1-Pyrroline-5-carboxylate dehydrogenase/ALDH4A1 PYCR1
arginine→	Ornithine aminotransferase Ornithine decarboxylase Agmatinase
→alpha-ketoglutarate→TCA	Glutamate dehydrogenase
Other	cysteine+glutamate→glutathione: Gamma-glutamylcysteine synthetase Glutathione synthetase Gamma-glutamyl transpeptidase glutamate→glutamine: Glutamine synthetase Glutaminase

G→propionyl-CoA→
succinyl-CoA

VALINE→	Branched-chain amino acid aminotransferase Branched-chain alpha-keto acid dehydrogenase complex Enoyl-CoA hydratase 3-hydroxyisobutyryl-CoA hydrolase 3-hydroxyisobutyrate dehydrogenase Methylmalonate semialdehyde dehydrogenase
ISOLEUCINE→	Branched-chain amino acid aminotransferase Branched-chain alpha-keto acid dehydrogenase complex 3-hydroxy-2-methylbutyryl-CoA dehydrogenase
METHIONINE→	generation of homocysteine: Methionine adenosyltransferase Adenosylhomocysteinase regeneration of methionine: Methionine synthase/Homocysteine methyltransferase Betaine-homocysteine methyltransferase conversion to cysteine: Cystathionine beta synthase Cystathionine gamma-lyase
THREONINE→	Threonine aldolase
→succinyl-CoA→TCA	Propionyl-CoA carboxylase Methylmalonyl CoA epimerase Methylmalonyl-CoA mutase

G→fumarate

PHENYLALANINE→tyrosine→	Phenylalanine hydroxylase Tyrosine aminotransferase 4-Hydroxyphenylpyruvate dioxygenase Homogentisate 1,2-dioxygenase Fumarylacetoacetate hydrolase tyrosine→melanin: Tyrosinase

G→oxaloacetate

asparagine→aspartate→	Asparaginase/Asparagine synthetase Aspartate transaminase

Purine metabolism

Anabolism

R5P→IMP:	Ribose-phosphate diphosphokinase Amidophosphoribosyltransferase Phosphoribosylglycinamide formyltransferase AIR synthetase (FGAM cyclase) Phosphoribosylaminoimidazole carboxylase Phosphoribosylaminoimidazolesuccinocarboxamide synthase IMP synthase
IMP→AMP:	Adenylosuccinate synthase Adenylosuccinate lyase reverse AMP deaminase
IMP→GMP:	IMP dehydrogenase GMP synthase reverse GMP reductase

Nucleotide salvage

Catabolism

Pyrimidine metabolism

Anabolism

CAD Carbamoyl phosphate synthase II Aspartate carbamoyltransferase Dihydroorotase
Dihydroorotate dehydrogenase Orotidine 5'-phosphate decarboxylase/Uridine monophosphate synthetase
CTP synthetase

Catabolism

Deoxyribonucleotides

Metabolism: lipid metabolism – ketones/cholesterol synthesis enzymes/steroid metabolism

Mevalonate pathway

To HMG-CoA	Acetyl-Coenzyme A acetyltransferase HMG-CoA synthase (regulated step)
Ketogenesis	HMG-CoA lyase 3-hydroxybutyrate dehydrogenase Thiophorase
To Mevalonic acid	HMG-CoA reductase
To DMAPP	Mevalonate kinase Phosphomevalonate kinase Pyrophosphomevalonate decarboxylase Isopentenyl-diphosphate delta isomerase
Geranyl-	Dimethylallyltranstransferase Geranyl pyrophosphate

To cholesterol

To lanosterol	Farnesyl-diphosphate farnesyltransferase Squalene monooxygenase Lanosterol synthase
7-Dehydrocholesterol path	Lanosterol 14α-demethylase Sterol-C5-desaturase-like 7-Dehydrocholesterol reductase
Desmosterol path	24-Dehydrocholesterol reductase

To Bile acids

Steroidogenesis

To pregnenolone

Cholesterol side-chain cleavage

To corticosteroids

aldosterone: 18-Hydroxylase

cortisol/cortisone: 17α-Hydroxylase
11β-HSD
- 1
- 2

To sex hormones

To androgens	17α-Hydroxylase 17,20-Lyase 3β-HSD 17β-HSD 5α-Reductase 1 2
To estrogens	Aromatase 17β-HSD

Other/ungrouped

v t e Metabolism: carbohydrate metabolism · pentose phosphate pathway enzymes
oxidative	Glucose-6-phosphate dehydrogenase 6-phosphogluconolactonase Phosphogluconate dehydrogenase
nonoxidative	Phosphopentose isomerase Phosphopentose epimerase Transketolase Transaldolase

v t e Metabolism - non-mevalonate pathway enzymes
DXP synthase DXP reductoisomerase 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol kinase 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase 4-hydroxy-3-methylbut-2-enyl diphosphate reductase

Food science

General

v t e Food preservation
Biopreservation Canning Cold chain Curing Drying Fermentation Freeze-drying Freezing Hurdle technology Irradiation Jamming Jellying Jugging Modified atmosphere Pascalization Pickling Potting Confit Potjevleesch Salting Smoking Sugaring Tyndallization Vacuum packing
Category: Food preservation

Food industry

v t e Consumer food safety
Adulterants, food contaminants	3-MCPD Aldicarb Antibiotic use in livestock Cyanide Formaldehyde HGH controversies Lead poisoning Melamine Mercury in fish Sudan I
Food additives	Flavorings Monosodium glutamate (MSG) Salt Sugar High-fructose corn syrup
Intestinal parasites and parasitic disease	Amoebiasis Anisakiasis Cryptosporidiosis Cyclosporiasis Diphyllobothriasis Enterobiasis Fasciolopsiasis Fasciolosis Giardiasis Gnathostomiasis Paragonimiasis Toxocariasis Toxoplasmosis Trichinosis Trichuriasis
Microorganisms	Botulism Campylobacter jejuni Clostridium perfringens Cronobacter Enterovirus Escherichia coli O104:H4 Escherichia coli O157:H7 Hepatitis A Hepatitis E Listeria Norovirus Rotavirus Salmonella Vibrio cholerae
Pesticides	Chlorpyrifos DDT Lindane Malathion Methamidophos
Preservatives	Benzoic acid Ethylenediaminetetraacetic acid (EDTA) Sodium benzoate
Sugar substitutes	Acesulfame potassium Aspartame controversy Saccharin Sodium cyclamate Sorbitol Sucralose
Toxins, poisons, environment pollution	Aflatoxin Arsenic contamination of groundwater Benzene in soft drinks Bisphenol A Dieldrin Diethylstilbestrol Dioxin Mycotoxins Nonylphenol Shellfish poisoning
Food processing	4-Hydroxynonenal Acid-hydrolyzed vegetable protein Acrylamide Creutzfeldt–Jakob disease Food additives Food irradiation Heterocyclic amines Modified starch Nitrosamines Polycyclic aromatic hydrocarbon Shortening Trans fat Water fluoridation controversy
Food contamination incidents	Devon colic Swill milk scandal Esing Bakery incident 1858 Bradford sweets poisoning 1900 English beer poisoning Morinaga Milk arsenic poisoning incident Minamata disease 1971 Iraq poison grain disaster Toxic oil syndrome 1985 Austrian diethylene glycol wine scandal United Kingdom BSE outbreak Australian meat substitution scandal 1993 Jack in the Box E. coli outbreak 1996 Odwalla E. coli outbreak 2006 North American E. coli outbreaks ICA meat repackaging controversy 2008 Canada listeriosis outbreak 2008 Chinese milk scandal 2008 Irish pork crisis 2008 United States salmonellosis outbreak 2011 Germany E. coli outbreak 2011 United States listeriosis outbreak 2013 Bihar school meal poisoning incident 2013 horse meat scandal 2015 Mozambique funeral beer poisoning 2017 Brazil Operation Weak Meat 2017–2018 South African listeriosis outbreak 2018 Australian rockmelon listeriosis outbreak 2018 Australian strawberry contamination Food safety incidents in China Food safety incidents in Taiwan Foodborne illness outbreaks death toll United States
Regulation, standards, watchdogs	Acceptable daily intake E number Food labeling regulations Food libel laws Food safety in Australia International Food Safety Network ISO 22000 Nutrition facts label Organic certification Quality Assurance International United Kingdom food information regulations
Institutions	Centre for Food Safety (Hong Kong) European Food Safety Authority Food and Drug Administration Food Information and Control Agency (Spain) Food Standards Agency (United Kingdom) Institute for Food Safety and Health International Food Safety Network Ministry of Food and Drug Safety (South Korea) Spanish Agency for Food Safety and Nutrition
Related topics	Curing (food preservation) Food and drink prohibitions Food marketing Food politics Food preservation Food quality Genetically modified food Conspiracy theories
Category Commons Cookbook WikiProject

v t e Artificial foods
Artificial fat substitutes	Olestra Trans fat
Artificial protein substitutes	Acid-hydrolyzed vegetable protein
Artificial sugar substitutes	Acesulfame potassium Alitame Aspartame Aspartame-acesulfame salt Dulcin Glucin Hydrogenated starch hydrolysates Neohesperidin dihydrochalcone Neotame NutraSweet Nutrinova Saccharin Sodium cyclamate Sucralose
Natural food substitutes	Cheese analogues Coffee substitutes Egg substitutes Meat analogues bacon list Milk substitutes Phyllodulcin Salt substitutes
Brands	Tang
Related topics	Food safety List of food additives

Food politics

Institutions