Bacterial cellulose biosynthesis

A species-neutral Gram-negative bacterial cellulose biosynthesis and export module covering BcsA cellulose polymerization, BcsB periplasmic accessory/regulatory support, BcsC outer-membrane export, and BcsQ/YhjQ-family accessory positioning where that P-loop NTPase is part of the local bcs locus. Pseudomonas putida KT2440 provides the current UniProt exemplars, but does not define the module boundary.

MODULE:bacterial_cellulose_biosynthesisDRAFTBiological Processmodules/bacterial_cellulose_biosynthesis.yaml
cellulose biosynthetic processGO:0030244
UniPathway:UPA00694
UniPathway UPA00694
The local UPA00694 membership set contains bcsA, bcsB, and PP_2638 as the KT2440 candidate genes for bacterial cellulose biosynthesis.
file:projects/P_PUTIDA/deep-research/PSEPK__cellulose_biosynthesis__upa00694-deep-research-openscientist.md
OpenScientist species-aware cellulose pathway research
OpenScientist concluded that UPA00694 is satisfiable in KT2440, that bcsA must be explicitly included despite the primary-bucket heuristic, and that PP_2634 is BcsQ/YhjQ rather than a second cellulose synthase.
file:modules/bacterial_cellulose_biosynthesis-deep-research-openscientist.md
OpenScientist module research for bacterial cellulose biosynthesis
OpenScientist summarized the conserved BcsA/BcsB/BcsC cellulose synthase/secretion architecture and the Pseudomonas-type bcs operon context.
GO:0030244
cellulose biosynthetic process
GO:0030244 is the biological-process term for formation of cellulose, a beta-1,4 glucan.
PMID:23222542
Crystallographic snapshot of cellulose synthesis and membrane translocation.
Primary structural evidence establishes BcsA as the catalytic inner-membrane subunit and BcsB as an inner-membrane-anchored periplasmic partner.
PMID:24704788
Mechanism of activation of bacterial cellulose synthase by cyclic di-GMP.
Primary structural evidence places the c-di-GMP PilZ-domain activation switch on BcsA.
PMID:31604608
Architecture of the Cellulose Synthase Outer Membrane Channel and Its Association with the Periplasmic TPR Domain.
Primary structural evidence defines BcsC as the beta-barrel outer-membrane cellulose secretion porin with a periplasmic TPR domain.
PMID:39242554
Insights into phosphoethanolamine cellulose synthesis and secretion across the Gram-negative cell envelope.
Cryo-EM evidence supports the BcsB-to-BcsC trans-envelope handoff for cellulose secretion.
file:PSEPK/bcsA/bcsA-uniprot.txt
UniProtKB entry for bcsA
UniProt describes BcsA as the cellulose synthase catalytic subunit that polymerizes UDP-glucose to cellulose and places it in bacterial cellulose biosynthesis.
file:PSEPK/bcsB/bcsB-uniprot.txt
UniProtKB entry for bcsB
UniProt describes BcsB as an AcsB/BcsB-family cellulose synthase regulatory/accessory subunit in bacterial cellulose biosynthesis.
file:PSEPK/PP_2638/PP_2638-uniprot.txt
UniProtKB entry for PP_2638
UniProt describes PP_2638 as a cellulose synthase operon C protein required for maximal bacterial cellulose synthesis.
file:PSEPK/PP_2634/PP_2634-uniprot.txt
UniProtKB entry for PP_2634
UniProt names PP_2634 generically as cellulose synthase, but its InterPro/Pfam/NCBIfam cross-references identify a BcsQ/YhjQ-family P-loop NTPase accessory protein.

Reusable boundary: this module represents the Bcs cellulose synthase/secretion core plus explicitly marked accessory BcsQ/YhjQ context, not every neighboring bcs-locus gene. The PSEPK instantiation is satisfiable: bcsA/Q88JL4 supplies UDP-forming cellulose synthase activity and the PilZ c-di-GMP switch, bcsB/Q88JL3 is the membrane-anchored periplasmic partner, PP_2638/Q88JL1 is the BcsC-like outer-membrane/export protein, and PP_2634/Q88JL5 should be treated as BcsQ/YhjQ accessory context rather than a second cellulose synthase. bcsZ, bcsR, and bcsF-like proteins remain broader module-boundary follow-up.

5Nodes
4Parts
0Variant Sets
0Variants
5Annotons
0Connections

Derived QC

Recommended-field compliance

53.8% recommended fields populated
  • module.knowledge_gaps[0] · status (0/1)
  • module.knowledge_gaps[0] · provenance (0/1)
  • module.knowledge_gaps[1] · status (0/1)
  • module.knowledge_gaps[1] · provenance (0/1)
  • module.knowledge_gaps[2] · status (0/1)
  • module.knowledge_gaps[2] · provenance (0/1)

Module deep research

✓ present

  • bacterial_cellulose_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 (4/4 grounded genes reviewed)

4 complete review(s) · 4 with deep research · 0 missing review · 0 reviewed but lacking deep research

Gene Review Complete Deep research
bcsA Q88JL4 ✓ ✓ ✓
bcsB Q88JL3 ✓ ✓ ✓
PP_2634 Q88JL5 ✓ ✓ ✓
PP_2638 Q88JL1 ✓ ✓ ✓

Details

Context
plasma membraneGO:0005886 outer membraneGO:0019867
Bacterial cellulose biosynthesisBiological Processbacterial_cellulose_biosynthesis
cellulose biosynthetic processGO:0030244
Context
plasma membraneGO:0005886 outer membraneGO:0019867
Part 1: Cellulose synthase catalytic subunit
BcsA cellulose polymerization stepReactionbcsA_cellulose_polymerization_step

BcsA is the multi-pass inner-membrane catalytic subunit that polymerizes UDP-glucose into cellulose.

Annotons

bcsA: cellulose synthase catalytic subunit
bcsA_cellulose_synthase
Participant: Family: BcsA cellulose synthase catalytic subunit family
Family:
BcsA cellulose synthase catalytic subunit familyInterPro:IPR003919
Representative Members: PSEPK bcsA exemplarUniProtKB:Q88JL4

Function

cellulose synthase (UDP-forming) activityGO:0016760

Processes

cellulose biosynthetic processGO:0030244

Locations

plasma membraneGO:0005886

Inner-membrane catalytic subunit that extends the cellulose beta-1,4-glucan chain from UDP-glucose.

bcsA: cyclic-di-GMP binding regulatory switch
bcsA_cyclic_di_gmp_binding
Participant: Family: BcsA PilZ-domain cellulose synthase family
Family:
BcsA PilZ-domain cellulose synthase familyInterPro:IPR003919
Representative Members: PSEPK bcsA exemplarUniProtKB:Q88JL4

Function

cyclic-di-GMP bindingGO:0035438

Processes

cellulose biosynthetic processGO:0030244

Locations

plasma membraneGO:0005886

PilZ-domain regulatory binding of cyclic di-GMP that activates BcsA-dependent cellulose synthesis.

Part 2: Cellulose synthase BcsB accessory/regulatory subunit
BcsB cellulose synthase regulatory stepRegulatory StepbcsB_cellulose_synthase_regulatory_step

BcsB is an inner-membrane-anchored periplasmic accessory/regulatory subunit associated with BcsA during c-di-GMP-controlled cellulose production.

Annotons

bcsB: cellulose synthase accessory subunit
bcsB_cellulose_synthase_accessory_subunit
Participant: Family: BcsB cellulose synthase accessory family
Family:
BcsB cellulose synthase accessory familyInterPro:IPR003920
Representative Members: PSEPK bcsB exemplarUniProtKB:Q88JL3

Processes

cellulose biosynthetic processGO:0030244

Locations

plasma membraneGO:0005886

Membrane-anchored periplasmic partner for BcsA that helps organize the Bcs cellulose synthase/secretion complex; direct c-di-GMP binding is kept with BcsA in this first-pass module.

Part 3: Cellulose synthase operon C export/support protein
BcsC cellulose export/support stepTransport Stepbcsc_cellulose_export_support_step

BcsC-like cellulose synthase operon C proteins form the outer-membrane/export-support part of the Gram-negative cellulose synthase/secretion system.

Annotons

BcsC family: cellulose synthase operon C protein
bcsc_cellulose_export_support
Participant: Family: BcsC cellulose export family
Family:
BcsC cellulose export familyInterPro:IPR008410
Representative Members: PSEPK PP_2638 exemplarUniProtKB:Q88JL1

Processes

cellulose biosynthetic processGO:0030244

Locations

outer membraneGO:0019867

Outer-membrane/export-support component needed for maximal bacterial cellulose synthesis; exact molecular activity is not assigned in this first pass.

Part 4: Accessory BcsQ/YhjQ positioning NTPase
BcsQ/YhjQ accessory stepRegulatory Stepbcsq_accessory_positioning_step

BcsQ/YhjQ-family P-loop NTPases are accessory/positioning factors in some bcs loci and should not be counted as catalytic cellulose synthases.

Annotons

BcsQ/YhjQ family: accessory factor
bcsq_accessory_factor
Participant: Family: BcsQ/YhjQ accessory P-loop NTPase family
Family:
BcsQ/YhjQ accessory P-loop NTPase familyInterPro:IPR017746
Representative Members: PSEPK PP_2634 exemplarUniProtKB:Q88JL5

Processes

cellulose biosynthetic processGO:0030244

BcsQ/YhjQ-family P-loop NTPase accessory/positioning factor inferred from InterPro IPR017746, Pfam PF06564, NCBIfam TIGR03371, and operon context.