Copyright © 2011-2014 by Mark Brandt, Ph.D.

Major Metabolic Pathways

Notes: Only regulatory enzymes are shown.

Red enzyme name and arrow = predominantly catabolic process Blue enzyme name and arrow = predominantly anabolic process Green compound name = branch-point compound Blue compound name = amino acid or ammonium

Glucose-6-phosphatedehydrogenase

Carbamoylphosphatesynthetase I

NH4

MitochondrialMatrix

Cytoplasm

Fructose-1,6-bisphosphate

Dihydroxy-acetone

phosphate

Glyceraldehyde3-phosphate

3-Phosphoglycerate

Phosphoenolpyruvate

Pyruvatekinase

L-Lactate

Phosphofructo-kinase

FADH2

CO2

CoA-SH

GTP

NADHNAD

+CoA-SH

GDP + Pi

FAD

CoA-SH

NAD

NADH

NADH

CO2

Acetyl-CoA

cis-Aconitate

Isocitrate

α-Ketoglutarate

Succinyl-CoA

Succinate

Citratesynthase

Isocitratedehydrogenase

+

α-Ketoglutaratedehydrogenase

+

TyrosinePhenylalanine

Heme

Propionyl-CoA

Glutamate

Isoleucine*Methionine

ValineThreonine*

Histidine Proline

Glutamine

Glu

tam

ina

se

NH4

Glutamine

Glu

tam

ine

syn

thet

ase

NH4

+ HCO3

Carbamoylphophate

Pi

Leucine*LysinePhenylalanine*Tryptophan*Tyrosine*

Glutamatedehydrogenase

orAminotransferase

Acetoacetyl-CoA

Ketonebodies

Isoleucine*Leucine*Threonine*

Fatty acids

CysteineGlycineSerineThreonine*Tryptophan*

Pyruvatecarboxylase

Pyruvatedehydrogenase

CO2

+ATP

CO2

NADH+

Pyruvate

NAD+ H2O

ADP+ Pi

ATP

Alanine

NAD

Fumarate

Malate

Oxaloacetate

Asparagine

Aspartate

β-oxidatio

n

Ele

ctro

ntr

an

spor

t

ATPsynthase

Ornithine

Ornithine

Arginine

UreaFumarate

Aspartate

Arginino-succinate

Citrulline

Citrulline

Malate

NADP

NADPH

Malic

enzy

me

Oxaloacetate

Pyruvate

Phosphoenolpyruvate

carboxykinase

Aspartate

Fumarate

Citrate lyase

Acetyl-CoA

Citrate

Citrate

Fatty acidsCholesterol

HMG-CoAReductase

Acetyl-CoAcarboxylase

Amino acidsTranscription

Translation

ProteinsUbiquitin conjugation,

Proteolysis

Amino acids

Glucose

Glycogen

Glucose-6-phosphate

Fructose-6-phosphate

Ribulose-5-phosphate

Fructose-6-phosphate+

Glyceraldehyde-3-phosphate

Ribose-5-phosphate

NADP NADPH

Serine Glycine

+

Glycerol

Glycerolphosphate

+

Fructose

CO2 +

HexokinaseGlucokinase

Glucose-6-phosphatase

Fructosebisphosphatase

NADP NADPH

GlycogenPhosphorylase

Glycogensynthase

GlutamineAspartateSer

ine

hydroxymethyl

transferase

N5, N10

MethyleneTHF

Glycinesynthase

Carbamoylphosphatesynthetase II

Ribose-5-phosphatepyrophosphokinase

PRPP Glutamylamidotransferase

Nucleotides

ReplicationandTranscription

Nucleic acids

Nucleases

O2

NADH+

Membranelipids

and

Triacylglycerols

Glycine

H

H

Protein foldingPost-translational modifications

H

HCO3

Cytoplasm MitochondrialMatrix