Compound

L,L-cystathionine

Dizwitterionic form of L-cystathionine arising from transfer of two protons from the carboxy to the amino groups; major species at pH 7.3.

Definition from ChEBI (CHEBI:58161), read 2026-09-23. CC BY 4.0.

CHEBI:58161ChEBI

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Structure

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A generated conformer of L,L-cystathionine — one low-energy arrangement PubChem computed, not a measured structure. Hydrogens are not drawn; the formula counts them.

Class: Organic compound
Formula: C7H14N2O4S
Mass: 222.266 g/mol
Charge: 0
InChIKey: ILRYLPWNYFXEMH-WHFBIAKZSA-N
SMILES: [NH3+][C@@H](CCSC[C@H]([NH3+])C(=O)[O-])C(=O)[O-]
Look it up: ChEBI PubChem By InChIKey

Identity from ChEBI, geometry from PubChem. Not evidence.

What it touches on the way

Mechanistic reach

3 entities

3 entities reached.

0 reported hops3 assembled from the scaffold

What the reference databases state

Statements

7 statements

7 statements · 2 reference databases · Subject: L,L-cystathionine · Sources: Human-GEM, Rhea

Order

homocysteine is converted to L,L-cystathionineCompoundHuman-GEM MAR03879Inferred only
L,L-cystathionine is converted to L-homocysteineCompoundRhea RHEA:10112Inferred only
L-homocysteine is converted to L,L-cystathionineCompoundRhea RHEA:10112Inferred only
L,L-cystathionine is a substrate of CBSProteinRhea RHEA:10112Inferred only
L,L-cystathionine is a substrate of CTHProteinHuman-GEM MAR03881Inferred only
L,L-cystathionine is a substrate of CTHProteinRhea RHEA:14005Inferred only
L,L-cystathionine is a substrate of NAGSProteinHuman-GEM MAR03922Inferred only

Reactions

15 reactions

homocysteine+L-seryl residuewater+L,L-cystathionine
Catalysed by CBS
Reaction pageLeft to rightBalancedEC 4.2.1.22cytosol
Human-GEM MAR03879CC BY 4.0Reference data
water+L,L-cystathionine2-oxobutanoate+L-cysteine+proton+ammonium
Catalysed by CTH
Reaction pageLeft to rightBalancedEC 4.4.1.1cytosol
Human-GEM MAR03881CC BY 4.0Reference data
L,L-cystathionineL,L-cystathionine
Reaction pageReversibleBalancedcytosol, mitochondrial matrix
Human-GEM MAR03921CC BY 4.0Reference data
CHEBI:1146900+proton+MAM02533mCHEBI:15351+L,L-cystathionine
Catalysed by NAGS
Reaction pageReversibleBalancedEC 2.3.1.1mitochondrial matrix
Human-GEM MAR03922CC BY 4.0Reference data
L,L-cystathionineL,L-cystathionine
Reaction pageReversibleBalancedextracellular space, cytosol
Human-GEM MAR09823CC BY 4.0Reference data
L,L-cystathionine
Reaction pageReversibleBalance undeterminableextracellular space
Human-GEM MAR09846CC BY 4.0Reference data
L-homocysteine+L-seryl residueL,L-cystathionine+water
Catalysed by CBS
Reaction pageDirection not assertedBalanced
Rhea RHEA:10112CC BY 4.0Reference data
L,L-cystathionine+waterL-homocysteine+pyruvate+ammonium
Reaction pageDirection not assertedBalanced
Rhea RHEA:13965CC BY 4.0Reference data
L,L-cystathionine+water2-oxobutanoate+L-cysteine+ammonium
Catalysed by CTH
Reaction pageLeft to rightBalanced
Rhea RHEA:14005CC BY 4.0Reference data
CHEBI:57661+L-cysteineL,L-cystathionine+succinate(2-)+hydron
Reaction pageDirection not assertedBalanced
Rhea RHEA:20397CC BY 4.0Reference data
L,L-cystathionineCHEBI:48306+L-cysteine
Reaction pageDirection not assertedBalanced
Rhea RHEA:24910CC BY 4.0Reference data
CHEBI:57716+L-cysteineL,L-cystathionine+acetate+hydron
Reaction pageDirection not assertedBalanced
Rhea RHEA:30931CC BY 4.0Reference data

Show the remaining 3

Other names

2 names

Resolves to: L,L-cystathionine

Also called: L-cystathionine zwitterion
Systematic name: (2R)-2-azaniumyl-4-{[(2R)-2-azaniumyl-2-carboxylatoethyl]sulfanyl}butanoate