Bacterial phosphatidylethanolamine biosynthesis through phosphatidylserine

A reusable two-reaction bacterial module for phosphatidylethanolamine biosynthesis from CDP-diacylglycerol. PssA transfers a phosphatidyl group to L-serine to form phosphatidylserine, and pyruvoyl-dependent Psd decarboxylates phosphatidylserine to phosphatidylethanolamine.

MODULE:bacterial_phosphatidylethanolamine_biosynthesisDRAFTCONCRETEMetabolic Pathwaymodules/bacterial_phosphatidylethanolamine_biosynthesis.yaml
phosphatidylethanolamine biosynthetic processGO:0006646
file:projects/P_PUTIDA/deep-research/PSEPK__bacterial_phosphatidylethanolamine_biosynthesis__ppu00564-deep-research-openscientist.md
OpenScientist review of the module, ppu00564, and PSEPK
The resolved module/pathway/taxon review finds both reactions covered, supports distinct Q88GQ4 and Q88DZ1 PssA architectures, and identifies paralog dominance rather than pathway satisfiability as the open issue.
file:modules/bacterial_phosphatidylethanolamine_biosynthesis-deep-research-openscientist.md
OpenScientist review of bacterial phosphatidylethanolamine biosynthesis
The generic module review evaluates the reusable two-reaction boundary, alternative PssA architectures, and Psd-dependent terminal reaction.
GO:0006646
phosphatidylethanolamine biosynthetic process
GO:0006646 captures biosynthesis of phosphatidylethanolamine.
RHEA:16913
CDP-diacylglycerol-serine O-phosphatidyltransferase reaction
Rhea 16913 defines formation of phosphatidylserine from CDP-diacylglycerol and L-serine.
RHEA:20828
phosphatidylserine decarboxylase reaction
Rhea 20828 defines decarboxylation of phosphatidylserine to phosphatidylethanolamine.
PMID:21895997
The glycerophospholipid inventory of Pseudomonas putida is conserved between strains and enables growth condition-related alterations
KT2440 lipidomics detects phosphatidylethanolamine as the major membrane phospholipid and reconstructs both pssA and pssA-2 candidates upstream of psd.
PMID:39693441
Structural basis for membrane association and catalysis by phosphatidylserine synthase in Escherichia coli
The primary structure study defines PLD-superfamily peripheral-membrane PssA as type I and integral-membrane CDP-alcohol phosphatidyltransferase PssA as type II.

The module begins with CDP-diacylglycerol and L-serine and ends with phosphatidylethanolamine. CDP-diacylglycerol synthesis, phosphatidylglycerol and cardiolipin branches, lipid acyl-chain remodeling, and alternative phosphatidylethanolamine routes such as the Kennedy pathway are outside the boundary. Psd autocatalytic maturation is required for activity but is a property of the terminal enzyme rather than a separate pathway reaction. Bacterial phosphatidylserine synthases occur in mechanistically distinct type-I and type-II architectures. These type names follow the PssA nomenclature of PMID:39693441; UniProt's CDP-alcohol phosphatidyltransferase class-I/class-II family labels describe a different classification axis and appear inverted relative to the PssA type names.

5Nodes
2Parts
1Variant Sets
2Variants
3Annotons
1Connections

Derived QC

Recommended-field compliance

100.0% recommended fields populated

All recommended fields populated.

Module deep research

✓ present

  • bacterial_phosphatidylethanolamine_biosynthesis-deep-research-openscientist.md (openscientist)

Leaf nodes lacking representative members

✓ every leaf node grounds to a representative protein.

Template conformance

✓ every declared conforms_to bundle matches its template motif.

Gene-review completeness (3/6 grounded genes reviewed)

3 complete review(s) · 3 with deep research · 3 missing review · 0 reviewed but lacking deep research

Gene Review Complete Deep research
Psd (Escherichia coli K-12) P0A8K1 ✗ — —
PssA (Escherichia coli K-12) P23830 ✗ — —
PssA (Bacillus subtilis 168) P39823 ✗ — —
PP_4677 Q88DZ1 ✓ ✓ ✓
psd Q88DB9 ✓ ✓ ✓
pssA Q88GQ4 ✓ ✓ ✓

Details

Context
bacteriaNCBITaxon:2
Bacterial phosphatidylethanolamine biosynthesisMetabolic Pathwaybacterial_phosphatidylethanolamine_biosynthesis
phosphatidylethanolamine biosynthetic processGO:0006646
Context
bacteriaNCBITaxon:2

Connections

PssA supplies phosphatidylserine to Psd.
Part 1: phosphatidylserine formation
PssA-dependent phosphatidylserine formationReactionpssa_phosphatidylserine_formation
Variant set: Bacterial phosphatidylserine synthase architecture by enzyme architecture (One Or More)
Type-I peripheral-membrane PssAReactiontype_i_pssa

Annotons

Type-I PssA phosphatidylserine synthase activity
type_i_pssa_activity
Participant: Family: type-I phosphatidylserine synthase PAINT lineage
Family:
type-I phosphatidylserine synthase PAINT lineagePANTHER:PTHR12586 PTHR12586 also contains eukaryotic PGS1 proteins; the required ancestral node restricts this annoton to the phosphatidylserine-synthase lineage.
Representative Members: PssA (Pseudomonas putida KT2440)UniProtKB:Q88GQ4 PssA (Escherichia coli K-12)UniProtKB:P23830

Function

CDP-diacylglycerol-serine O-phosphatidyltransferase activityGO:0003882
Substrates: CDP-diacylglycerol L-serine
Products: phosphatidylserine CMP proton

Processes

phosphatidylethanolamine biosynthetic processGO:0006646

Locations

plasma membraneGO:0005886

Supplies phosphatidylserine to Psd.

Type-II integral-membrane PssAReactiontype_ii_pssa

Annotons

Type-II PssA phosphatidylserine synthase activity
type_ii_pssa_activity
Participant: Family: type-II phosphatidylserine synthase family
Family:
type-II phosphatidylserine synthase familyInterPro:IPR004533
Representative Members: PP_4677 (Pseudomonas putida KT2440)UniProtKB:Q88DZ1 PssA (Bacillus subtilis 168)UniProtKB:P39823

Function

CDP-diacylglycerol-serine O-phosphatidyltransferase activityGO:0003882
Substrates: CDP-diacylglycerol L-serine
Products: phosphatidylserine CMP proton

Processes

phosphatidylethanolamine biosynthetic processGO:0006646

Locations

plasma membraneGO:0005886

Supplies phosphatidylserine to Psd.

Part 2: phosphatidylethanolamine formation
Psd-dependent phosphatidylethanolamine formationReactionpsd_phosphatidylethanolamine_formation

Annotons

Psd phosphatidylserine decarboxylase activity
psd_activity
Participant: Family: phosphatidylserine decarboxylase family
Family:
phosphatidylserine decarboxylase familyPANTHER:PTHR10067
Representative Members: Psd (Pseudomonas putida KT2440)UniProtKB:Q88DB9 Psd (Escherichia coli K-12)UniProtKB:P0A8K1

Function

phosphatidylserine decarboxylase activityGO:0004609
Substrates: phosphatidylserine proton
Products: phosphatidylethanolamine carbon dioxide

Processes

phosphatidylethanolamine biosynthetic processGO:0006646

Locations

plasma membraneGO:0005886

Completes phosphatidylethanolamine biosynthesis.