L-arginine biosynthesis via acetylated ornithineMetabolic Pathwayarginine_biosynthesis
Molecular functions are attached only to leaf annotons. The module-level concept is the biological process, and no generic cytoplasmic location is asserted. Exact PSEPK UniProt accessions ground each family selector without making the reusable reaction architecture species-specific. PAINT nodes are attached only where a local IBD row names a reviewed molecular-function exemplar; they do not establish species-specific pathway usage. Shared carbamoyl-phosphate production and unrelated arginine catabolism are outside this module.
Connections
Part 1: pathway-initiating glutamate acetylation
L-glutamate to N-acetyl-L-glutamateReactionglutamate_acetylation_step
The initial acetylation can be supplied by a dedicated ArgA enzyme or by the bifunctional ArgJ enzyme used in cyclic acetyl transfer.
Variant set: Glutamate acetylation enzyme variants by enzyme family (One Or More)
Dedicated ArgA implementationReactionargA_initiation_variant
Annotons
ArgA N-acetylglutamate synthase
argA_activity
Participant: Family: ArgA N-acetylglutamate synthase family
Family:
ArgA N-acetylglutamate synthase familyNCBIfam:TIGR01890
Required Function:
L-glutamate N-acetyltransferase activity, acting on acetyl-CoA as donorGO:0004042
Function
L-glutamate N-acetyltransferase activity, acting on acetyl-CoA as donorGO:0004042
Substrates:
L-glutamate
acetyl-CoA
Products:
N-acetyl-L-glutamate
CoA
Dedicated enzyme for the first reaction of the linear route.
Bifunctional ArgJ initiation implementationReactionargJ_initiation_variant
Annotons
ArgJ acetyl-CoA-dependent initiating activity
argJ_initiating_activity
Participant: Family: bifunctional ArgJ family
Family:
bifunctional ArgJ familyNCBIfam:TIGR00120
Required Function:
L-glutamate N-acetyltransferase activity, acting on acetyl-CoA as donorGO:0004042
Function
L-glutamate N-acetyltransferase activity, acting on acetyl-CoA as donorGO:0004042
Substrates:
L-glutamate
acetyl-CoA
Products:
N-acetyl-L-glutamate
CoA
Initiating activity of bifunctional ArgJ; the same protein can recycle the acetyl group at the ornithine-release step.
Part 2: acetylglutamate kinase
N-acetyl-L-glutamate to N-acetyl-L-glutamyl 5-phosphateReactionacetylglutamate_kinase_step
Annotons
ArgB acetylglutamate kinase
argB_activity
Participant: Family: ArgB acetylglutamate kinase family
Family:
ArgB acetylglutamate kinase familyNCBIfam:TIGR00761
Function
acetylglutamate kinase activityGO:0003991
Substrates:
N-acetyl-L-glutamate
ATP
Products:
N-acetyl-L-glutamyl 5-phosphate
ADP
Activates the acetylated glutamate carboxyl group for reduction.
Part 3: acetylglutamyl-phosphate reductase
N-acetyl-L-glutamyl 5-phosphate to N-acetyl-L-glutamate 5-semialdehydeReactionacetylglutamyl_phosphate_reductase_step
Type 1 and type 2 ArgC proteins are structurally distinct family implementations of the same NADPH-dependent reaction.
Variant set: ArgC reductase family variants by enzyme family (One Or More)
Type 1 ArgC implementationReactionargC_type1_variant
Annotons
Type 1 ArgC reductase
argC1_activity
Participant: Family: type 1 ArgC family
Family:
type 1 ArgC familyNCBIfam:TIGR01850
Required Function:
N-acetyl-gamma-glutamyl-phosphate reductase activityGO:0003942
Function
N-acetyl-gamma-glutamyl-phosphate reductase activityGO:0003942
Substrates:
N-acetyl-L-glutamyl 5-phosphate
NADPH
proton
Products:
N-acetyl-L-glutamate 5-semialdehyde
phosphate
NADP+
Type 1 family implementation of the ArgC reaction.
Type 2 ArgC implementationReactionargC_type2_variant
Annotons
Type 2 ArgC reductase
argC2_activity
Participant: Family: type 2 ArgC family
Family:
type 2 ArgC familyNCBIfam:TIGR01851
Required Function:
N-acetyl-gamma-glutamyl-phosphate reductase activityGO:0003942
Function
N-acetyl-gamma-glutamyl-phosphate reductase activityGO:0003942
Substrates:
N-acetyl-L-glutamyl 5-phosphate
NADPH
proton
Products:
N-acetyl-L-glutamate 5-semialdehyde
phosphate
NADP+
Type 2 family implementation of the ArgC reaction.
Part 4: acetylornithine aminotransferase
N-acetyl-L-glutamate 5-semialdehyde to N-acetyl-L-ornithineReactionacetylornithine_aminotransferase_step
Annotons
ArgD acetylornithine aminotransferase
argD_activity
Participant: Family: anabolic ArgD-like acetylornithine aminotransferase family
Required Function:
N2-acetyl-L-ornithine:2-oxoglutarate 5-transaminase activityGO:0003992
Function
N2-acetyl-L-ornithine:2-oxoglutarate 5-transaminase activityGO:0003992
Substrates:
N-acetyl-L-glutamate 5-semialdehyde
L-glutamate
Products:
N-acetyl-L-ornithine
2-oxoglutarate
Cofactors:
pyridoxal 5'-phosphate
Forms the activated ornithine intermediate by PLP-dependent transamination. AstC-like succinylornithine transaminases can show overlapping ACOAT activity, but catabolic-operon membership alone does not make them the preferred biosynthetic implementation.
Part 5: ornithine release
N-acetyl-L-ornithine to L-ornithineReactionornithine_release_step
Ornithine is released either by ArgJ-mediated transfer of the acetyl group back to glutamate or by ArgE-mediated hydrolysis.
Variant set: Ornithine-release enzyme variants by reaction mechanism (One Or More)
Cyclic ArgJ transacetylationReactionargJ_transacetylation_variant
Annotons
ArgJ ornithine acetyltransferase
argJ_recycling_activity
Participant: Family: bifunctional ArgJ family
Family:
bifunctional ArgJ familyNCBIfam:TIGR00120
Required Function:
L-glutamate N-acetyltransferase activity, acting on acetyl-L-ornithine as donorGO:0004358
Function
L-glutamate N-acetyltransferase activity, acting on acetyl-L-ornithine as donorGO:0004358
Substrates:
N-acetyl-L-ornithine
L-glutamate
Products:
L-ornithine
N-acetyl-L-glutamate
Releases ornithine while regenerating N-acetyl-L-glutamate for the cyclic route.
Hydrolytic ArgE deacetylationReactionargE_deacetylation_variant
Annotons
ArgE acetylornithine deacetylase
argE_activity
Participant: Family: ArgE acetylornithine deacetylase family
Family:
ArgE acetylornithine deacetylase familyNCBIfam:TIGR01892
Function
acetylornithine deacetylase activityGO:0008777
Substrates:
N-acetyl-L-ornithine
water
Products:
L-ornithine
acetate
Releases ornithine by hydrolysis in the linear route.
Part 6: ornithine carbamoyltransferase
L-ornithine to L-citrullineReactionornithine_carbamoyltransferase_step
Annotons
Biosynthetic ornithine carbamoyltransferase
argF_activity
Participant: Family: biosynthetic ArgF ornithine carbamoyltransferase family
Family:
biosynthetic ArgF ornithine carbamoyltransferase familyInterPro:IPR024904
Function
ornithine carbamoyltransferase activityGO:0004585
Substrates:
L-ornithine
carbamoyl phosphate
Products:
L-citrulline
phosphate
First reaction after ornithine formation; family selection distinguishes biosynthetic ArgF/ArgI enzymes from catabolic ArcB.
Part 7: argininosuccinate synthase
L-citrulline to argininosuccinateReactionargininosuccinate_synthase_step
Annotons
ArgG argininosuccinate synthase
argG_activity
Participant: Family: type 1 ArgG argininosuccinate synthase family
Family:
type 1 ArgG argininosuccinate synthase familyNCBIfam:TIGR00032
Function
argininosuccinate synthase activityGO:0004055
Substrates:
L-citrulline
L-aspartate
ATP
Products:
argininosuccinate
AMP
diphosphate
Incorporates aspartate nitrogen into the arginine precursor.
Part 8: terminal argininosuccinate lyase
Argininosuccinate to L-arginineReactionargininosuccinate_lyase_step
Annotons
ArgH argininosuccinate lyase
argH_activity
Participant: Family: ArgH argininosuccinate lyase family
Family:
ArgH argininosuccinate lyase familyNCBIfam:TIGR00838
Function
argininosuccinate lyase activityGO:0004056
Substrates:
argininosuccinate
Products:
L-arginine
fumarate
Produces L-arginine in the terminal pathway reaction.