Phosphorylation of glucose
One ATP is spent to add a phosphate to glucose. The charged phosphate traps glucose inside the cell.
Glycolysis · irreversibleBUILD UP YOUR UNDERSTANDING
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28 linksConnected records
Used and produced inGlycolysisUsed inGluconeogenesisProduced inOxidative phosphorylationUsed inFatty acid synthesisUsed inCholesterol biosynthesisUsed inUrea cycleUsed inPurine nucleotide synthesisUsed inPyrimidine nucleotide synthesis
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Handled byHexokinaseHandled byPhosphofructokinase-1Handled byPhosphoglycerate kinaseHandled byPyruvate kinaseHandled byPyruvate carboxylaseHandled byATP synthase (complex V)Handled byATP-citrate lyaseHandled byAcetyl-CoA carboxylaseHandled byMevalonate kinaseHandled byPhosphomevalonate kinaseHandled byMevalonate diphosphate decarboxylaseHandled byCarbamoyl-phosphate synthetase IHandled byArgininosuccinate synthaseHandled byRibose-phosphate pyrophosphokinaseHandled byGAR synthetaseHandled byFGAM synthetaseHandled byAIR synthetaseHandled bySAICAR synthetaseHandled byGMP branch enzymesHandled byCAD multifunctional enzyme
STRUCTURED REACTIONS
Open metabolism map Where it appears
Phosphorylation of fructose 6-phosphate
A second ATP adds a phosphate to carbon 1. This commits the sugar to glycolysis and is the pathway's main control point.
Glycolysis · irreversibleFirst ATP-generating step
1,3-Bisphosphoglycerate gives a phosphate to ADP and makes ATP. Across both three-carbon halves, this repays the two ATP invested.
Glycolysis · reversibleSecond ATP-generating step
PEP gives its phosphate to ADP, forming ATP and pyruvate. This second ATP-making step is where glycolysis turns a net profit.
Glycolysis · irreversibleCarboxylation of pyruvate
Pyruvate gains a carbon dioxide equivalent to form oxaloacetate, using ATP and biotin.
Gluconeogenesis · irreversibleATP synthesis by chemiosmosis
ATP synthase uses proton flow to drive ATP formation from ADP and phosphate.
Oxidative phosphorylation · irreversibleShow 16 more reaction records
Cytosolic acetyl-CoA supply
ATP-citrate lyase provides cytosolic acetyl-CoA from exported citrate.
Fatty acid synthesis · irreversibleMalonyl-CoA formation
Acetyl-CoA carboxylase uses ATP and biotin to make malonyl-CoA.
Fatty acid synthesis · irreversibleMevalonate phosphorylation
Mevalonate kinase phosphorylates mevalonate.
Cholesterol biosynthesis · irreversibleSecond phosphorylation
Phosphomevalonate kinase makes mevalonate 5-diphosphate.
Cholesterol biosynthesis · irreversibleIsopentenyl diphosphate formation
Mevalonate diphosphate decarboxylase produces the five-carbon isoprene unit IPP.
Cholesterol biosynthesis · irreversibleCarbamoyl phosphate synthesis
CPS1 uses two ATP to combine ammonia and bicarbonate into carbamoyl phosphate.
Urea cycle · irreversibleArgininosuccinate formation
Argininosuccinate synthase joins citrulline to aspartate, using ATP to AMP.
Urea cycle · irreversiblePRPP formation
PRPP synthetase activates ribose 5-phosphate using ATP.
Purine nucleotide synthesis · irreversibleGlutamine-dependent nitrogen addition
FGAM synthetase supplies another ring nitrogen from glutamine.
Purine nucleotide synthesis · irreversibleImidazole ring closure
AIR synthetase closes the first purine ring.
Purine nucleotide synthesis · irreversibleAspartate addition
SAICAR synthetase adds aspartate to CAIR using ATP.
Purine nucleotide synthesis · irreversibleGMP branch
The GMP branch oxidizes IMP to XMP and adds nitrogen from glutamine using ATP.
Purine nucleotide synthesis · irreversibleCarbamoyl phosphate formation
The CAD enzyme complex forms cytosolic carbamoyl phosphate from glutamine and bicarbonate.
Pyrimidine nucleotide synthesis · irreversibleAspartate addition and ring closure
CAD adds aspartate and closes the ring to form dihydroorotate.
Pyrimidine nucleotide synthesis · irreversibleUTP and CTP formation
Downstream phosphorylation and CTP synthetase convert UMP through UDP and UTP, then make CTP.
Pyrimidine nucleotide synthesis · irreversible