pyridoxal 5'-phosphate biosynthesis I
MetaCyc:PYRIDOXSYN-PWY
The DXP-dependent pyridoxal 5'-phosphate biosynthesis I pathway oxidizes D-erythrose 4-phosphate to 4-phospho-D-erythronate, transaminates the resulting keto acid to 4-(phosphooxy)-L-threonine, decarboxylates it to 3-amino-2-oxopropyl phosphate, condenses that intermediate with 1-deoxy-D-xylulose 5-phosphate to form pyridoxine 5'-phosphate, and oxidizes pyridoxine 5'-phosphate to pyridoxal 5'-phosphate.
- Pathway type
- cofactor biosynthesis
- Organism scope
Pathway network
47 nodes · 67 asserted directed edges
Arrows show recorded subject → object relationships, not necessarily metabolic flow. Select a node for details or an arrow for evidence. Scroll, zoom or find a node to explore.
- Reaction / activity
- Chemical / cofactor
- Protein / complex
- Other participant
- Cell / process context
- Solid arrow: mechanistic relation
- Dashed arrow: membership, location or cofactor relation
Components and activities
| Node | Kind or role | Source direction |
|---|---|---|
Escherichia coliNCBITaxon:562 | taxon | |
erythrose-4-phosphate dehydrogenaseEC:1.2.1.72 | molecular activity | |
4-phosphoerythronate dehydrogenaseEC:1.1.1.290 | molecular activity | |
phosphoserine transaminaseEC:2.6.1.52 | molecular activity | |
4-hydroxythreonine-4-phosphate dehydrogenaseEC:1.1.1.262 | molecular activity | |
1-deoxy-D-xylulose-5-phosphate synthaseEC:2.2.1.7 | molecular activity | |
pyridoxine 5'-phosphate synthaseEC:2.6.99.2 | molecular activity | |
pyridoxine 5'-phosphate oxidaseEC:1.4.3.5 | molecular activity | |
D-erythrose 4-phosphateCHEBI:16897 | small molecule | |
NAD(+)CHEBI:57540 | small molecule | |
H2OCHEBI:15377 | small molecule | |
4-phospho-D-erythronateCHEBI:58766 | small molecule | |
NADHCHEBI:57945 | small molecule | |
H(+)CHEBI:15378 | small molecule | |
(R)-3-hydroxy-2-oxo-4-phosphooxybutanoateCHEBI:58538 | small molecule | |
L-glutamateCHEBI:29985 | small molecule | |
4-(phosphooxy)-L-threonineCHEBI:58452 | small molecule | |
2-oxoglutarateCHEBI:16810 | small molecule | |
3-amino-2-oxopropyl phosphateCHEBI:57279 | small molecule | |
CO2CHEBI:16526 | small molecule | |
D-glyceraldehyde 3-phosphateCHEBI:59776 | small molecule | |
pyruvateCHEBI:15361 | small molecule | |
1-deoxy-D-xylulose 5-phosphateCHEBI:57792 | small molecule | |
pyridoxine 5'-phosphateCHEBI:58589 | small molecule | |
phosphateCHEBI:43474 | small molecule | |
O2CHEBI:15379 | small molecule | |
pyridoxal 5'-phosphateCHEBI:597326 | cofactor | |
H2O2CHEBI:16240 | small molecule | |
Erythronate-4-phosphate dehydrogenaseUniProtKB:P05459 | protein | |
cytoplasmGO:0005737 | cellular component | |
Pyridoxine 5'-phosphate synthaseUniProtKB:P0A794 | protein | |
D-erythrose-4-phosphate dehydrogenaseUniProtKB:P0A9B6 | protein | |
Pyridoxine/pyridoxamine 5'-phosphate oxidaseUniProtKB:P0AFI7 | protein | |
FMN(3-)CHEBI:58210 | cofactor | |
4-hydroxythreonine-4-phosphate dehydrogenaseUniProtKB:P19624 | protein | |
zinc(2+)CHEBI:29105 | cofactor | |
magnesium(2+)CHEBI:18420 | cofactor | |
cobalt(2+)CHEBI:48828 | cofactor | |
Phosphoserine aminotransferaseUniProtKB:P23721 | protein | |
1-deoxy-D-xylulose-5-phosphate synthaseUniProtKB:P77488 | protein | |
thiamine(1+) diphosphate(3-)CHEBI:58937 | cofactor | |
erythrose-4-phosphate dehydrogenase reactionRHEA:12057 | reaction | left to right |
4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 | reaction | left to right |
phosphoserine transaminase reactionRHEA:16575 | reaction | right to left |
4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 | reaction | left to right |
1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 | reaction | left to right |
pyridoxine 5'-phosphate synthase reactionRHEA:15266 | reaction | left to right |
pyridoxine 5'-phosphate oxidase reactionRHEA:15150 | reaction | left to right |
Mechanistic edges
| Subject | Predicate and description | Object | Evidence |
|---|---|---|---|
H2OCHEBI:15377 | consumes | erythrose-4-phosphate dehydrogenase reactionRHEA:12057 |
|
D-erythrose 4-phosphateCHEBI:16897 | consumes | erythrose-4-phosphate dehydrogenase reactionRHEA:12057 |
|
NAD(+)CHEBI:57540 | consumes | erythrose-4-phosphate dehydrogenase reactionRHEA:12057 |
|
erythrose-4-phosphate dehydrogenase reactionRHEA:12057 | produces | H(+)CHEBI:15378 |
|
erythrose-4-phosphate dehydrogenase reactionRHEA:12057 | produces | NADHCHEBI:57945 |
|
erythrose-4-phosphate dehydrogenase reactionRHEA:12057 | produces | 4-phospho-D-erythronateCHEBI:58766 |
|
NAD(+)CHEBI:57540 | consumes | 4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 |
|
4-phospho-D-erythronateCHEBI:58766 | consumes | 4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 |
|
4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 | produces | H(+)CHEBI:15378 |
|
4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 | produces | NADHCHEBI:57945 |
|
4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 | produces | (R)-3-hydroxy-2-oxo-4-phosphooxybutanoateCHEBI:58538 |
|
L-glutamateCHEBI:29985 | consumes | phosphoserine transaminase reactionRHEA:16575 |
|
(R)-3-hydroxy-2-oxo-4-phosphooxybutanoateCHEBI:58538 | consumes | phosphoserine transaminase reactionRHEA:16575 |
|
phosphoserine transaminase reactionRHEA:16575 | produces | 2-oxoglutarateCHEBI:16810 |
|
phosphoserine transaminase reactionRHEA:16575 | produces | 4-(phosphooxy)-L-threonineCHEBI:58452 |
|
NAD(+)CHEBI:57540 | consumes | 4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 |
|
4-(phosphooxy)-L-threonineCHEBI:58452 | consumes | 4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 |
|
4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 | produces | CO2CHEBI:16526 |
|
4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 | produces | 3-amino-2-oxopropyl phosphateCHEBI:57279 |
|
4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 | produces | NADHCHEBI:57945 |
|
pyruvateCHEBI:15361 | consumes | 1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 |
|
H(+)CHEBI:15378 | consumes | 1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 |
|
D-glyceraldehyde 3-phosphateCHEBI:59776 | consumes | 1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 |
|
1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 | produces | CO2CHEBI:16526 |
|
1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 | produces | 1-deoxy-D-xylulose 5-phosphateCHEBI:57792 |
|
3-amino-2-oxopropyl phosphateCHEBI:57279 | consumes | pyridoxine 5'-phosphate synthase reactionRHEA:15266 |
|
1-deoxy-D-xylulose 5-phosphateCHEBI:57792 | consumes | pyridoxine 5'-phosphate synthase reactionRHEA:15266 |
|
pyridoxine 5'-phosphate synthase reactionRHEA:15266 | produces | H2OCHEBI:15377 |
|
pyridoxine 5'-phosphate synthase reactionRHEA:15266 | produces | H(+)CHEBI:15378 |
|
pyridoxine 5'-phosphate synthase reactionRHEA:15266 | produces | phosphateCHEBI:43474 |
|
pyridoxine 5'-phosphate synthase reactionRHEA:15266 | produces | pyridoxine 5'-phosphateCHEBI:58589 |
|
O2CHEBI:15379 | consumes | pyridoxine 5'-phosphate oxidase reactionRHEA:15150 |
|
pyridoxine 5'-phosphateCHEBI:58589 | consumes | pyridoxine 5'-phosphate oxidase reactionRHEA:15150 |
|
pyridoxine 5'-phosphate oxidase reactionRHEA:15150 | produces | H2O2CHEBI:16240 |
|
pyridoxine 5'-phosphate oxidase reactionRHEA:15150 | produces | pyridoxal 5'-phosphateCHEBI:597326 |
|
erythrose-4-phosphate dehydrogenaseEC:1.2.1.72 | catalyzes | erythrose-4-phosphate dehydrogenase reactionRHEA:12057 |
|
4-phosphoerythronate dehydrogenaseEC:1.1.1.290 | catalyzes | 4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 |
|
phosphoserine transaminaseEC:2.6.1.52 | catalyzes | phosphoserine transaminase reactionRHEA:16575 |
|
4-hydroxythreonine-4-phosphate dehydrogenaseEC:1.1.1.262 | catalyzes | 4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 |
|
1-deoxy-D-xylulose-5-phosphate synthaseEC:2.2.1.7 | catalyzes | 1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 |
|
pyridoxine 5'-phosphate synthaseEC:2.6.99.2 | catalyzes | pyridoxine 5'-phosphate synthase reactionRHEA:15266 |
|
pyridoxine 5'-phosphate oxidaseEC:1.4.3.5 | catalyzes | pyridoxine 5'-phosphate oxidase reactionRHEA:15150 |
|
erythrose-4-phosphate dehydrogenase reactionRHEA:12057 | precedes | 4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 |
|
1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 | precedes | pyridoxine 5'-phosphate synthase reactionRHEA:15266 |
|
pyridoxine 5'-phosphate synthase reactionRHEA:15266 | precedes | pyridoxine 5'-phosphate oxidase reactionRHEA:15150 |
|
phosphoserine transaminase reactionRHEA:16575 | precedes | 4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 |
|
4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 | precedes | phosphoserine transaminase reactionRHEA:16575 |
|
4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 | precedes | pyridoxine 5'-phosphate synthase reactionRHEA:15266 |
|
Erythronate-4-phosphate dehydrogenaseUniProtKB:P05459 | enables | 4-phospho-D-erythronate dehydrogenase reactionRHEA:18830 |
|
Erythronate-4-phosphate dehydrogenaseUniProtKB:P05459 | located_in | cytoplasmGO:0005737 |
|
Pyridoxine 5'-phosphate synthaseUniProtKB:P0A794 | enables | pyridoxine 5'-phosphate synthase reactionRHEA:15266 |
|
Pyridoxine 5'-phosphate synthaseUniProtKB:P0A794 | located_in | cytoplasmGO:0005737 |
|
D-erythrose-4-phosphate dehydrogenaseUniProtKB:P0A9B6 | enables | erythrose-4-phosphate dehydrogenase reactionRHEA:12057 |
|
D-erythrose-4-phosphate dehydrogenaseUniProtKB:P0A9B6 | located_in | cytoplasmGO:0005737 |
|
Pyridoxine/pyridoxamine 5'-phosphate oxidaseUniProtKB:P0AFI7 | enables | pyridoxine 5'-phosphate oxidase reactionRHEA:15150 |
|
Pyridoxine/pyridoxamine 5'-phosphate oxidaseUniProtKB:P0AFI7 | has_cofactor | FMN(3-)CHEBI:58210 |
|
4-hydroxythreonine-4-phosphate dehydrogenaseUniProtKB:P19624 | enables | 4-hydroxythreonine-4-phosphate dehydrogenase reactionRHEA:32276 |
|
4-hydroxythreonine-4-phosphate dehydrogenaseUniProtKB:P19624 | located_in | cytoplasmGO:0005737 |
|
4-hydroxythreonine-4-phosphate dehydrogenaseUniProtKB:P19624 | has_cofactor | zinc(2+)CHEBI:29105 |
|
4-hydroxythreonine-4-phosphate dehydrogenaseUniProtKB:P19624 | has_cofactor | magnesium(2+)CHEBI:18420 |
|
4-hydroxythreonine-4-phosphate dehydrogenaseUniProtKB:P19624 | has_cofactor | cobalt(2+)CHEBI:48828 |
|
Phosphoserine aminotransferaseUniProtKB:P23721 | enables | phosphoserine transaminase reactionRHEA:16575 |
|
Phosphoserine aminotransferaseUniProtKB:P23721 | located_in | cytoplasmGO:0005737 |
|
Phosphoserine aminotransferaseUniProtKB:P23721 | has_cofactor | pyridoxal 5'-phosphateCHEBI:597326 |
|
1-deoxy-D-xylulose-5-phosphate synthaseUniProtKB:P77488 | enables | 1-deoxy-D-xylulose-5-phosphate synthase reactionRHEA:12606 |
|
1-deoxy-D-xylulose-5-phosphate synthaseUniProtKB:P77488 | has_cofactor | magnesium(2+)CHEBI:18420 |
|
1-deoxy-D-xylulose-5-phosphate synthaseUniProtKB:P77488 | has_cofactor | thiamine(1+) diphosphate(3-)CHEBI:58937 |
|
References
MetaCyc:PYRIDOXSYN-PWYMetaCyc pyridoxal 5'-phosphate biosynthesis I pathway (source version: 22.5)RHEA:12056Rhea erythrose-4-phosphate dehydrogenase reaction (source version: 139)RHEA:12057Rhea 4-phospho-D-erythronate-forming direction (source version: 139)RHEA:18829Rhea 4-phospho-D-erythronate dehydrogenase reaction (source version: 139)RHEA:18830Rhea (R)-3-hydroxy-2-oxo-4-phosphooxybutanoate-forming direction (source version: 139)RHEA:16573Rhea phosphoserine transaminase reaction (source version: 139)RHEA:16575Rhea 4-(phosphooxy)-L-threonine-forming direction (source version: 139)RHEA:32275Rhea 4-hydroxythreonine-4-phosphate dehydrogenase reaction (source version: 139)RHEA:32276Rhea 3-amino-2-oxopropyl phosphate-forming direction (source version: 139)RHEA:12605Rhea 1-deoxy-D-xylulose-5-phosphate synthase reaction (source version: 139)RHEA:12606Rhea 1-deoxy-D-xylulose 5-phosphate-forming direction (source version: 139)RHEA:15265Rhea pyridoxine 5'-phosphate synthase reaction (source version: 139)RHEA:15266Rhea pyridoxine 5'-phosphate-forming direction (source version: 139)RHEA:15149Rhea pyridoxine 5'-phosphate oxidase reaction (source version: 139)RHEA:15150Rhea pyridoxal 5'-phosphate-forming direction (source version: 139)UniProtKB:P05459UniProtKB:P05459 authority record (source version: 2026_03)UniProtKB:P0A794UniProtKB:P0A794 authority record (source version: 2026_03)UniProtKB:P0A9B6UniProtKB:P0A9B6 authority record (source version: 2026_03)UniProtKB:P0AFI7UniProtKB:P0AFI7 authority record (source version: 2026_03)UniProtKB:P19624UniProtKB:P19624 authority record (source version: 2026_03)UniProtKB:P23721UniProtKB:P23721 authority record (source version: 2026_03)UniProtKB:P77488UniProtKB:P77488 authority record (source version: 2026_03)
Curation history
- codex
- EDIT — Review causal chemistry and add sourced molecular context
Reviewed the entire record against MetaCyc 22.5 native pathway XML (including nested pathways), Rhea 139 explicit sides and directions, ENZYME 02-Sep-2026, PubMed records, and reviewed UniProt 2026_03 annotations within the record's taxon scope. Replaced generated structured-source quotations with source_assertion and source_locator. Typed molecular activities and participants. Reaction count 7 to 7; 0 directed-ID corrections; 7 protein annotations, 7 cofactor annotations and 5 sourced locations. All Rhea reaction substrate/product sets checked against independent Rhea authority; native pathway leaf coverage and source exceptions recorded in reports/causal_graph_review/metacyc-review.json. Full source URLs, versions and byte hashes are in metacyc-sources.json. All 50 MetaCyc records passed native schema validation; six targeted chemistry/evidence regression tests passed. Missing protein or cofactor annotations are not treated as biological absence; qualifications and exclusions are preserved in the ledger.
- EDIT — Review causal chemistry and add sourced molecular context