Bacterial alkanesulfonate uptake and FMN-dependent desulfonation

A reusable bacterial sulfur-scavenging module in which the SsuABC ABC transporter imports aliphatic sulfonates, SsuE reduces FMN using NADPH, and SsuD uses reduced FMN and oxygen to release sulfite from an alkanesulfonate. Sulfite assimilation, substrate-specific transport paralogs, and regulatory responses to sulfur limitation are outside the module boundary.

MODULE:bacterial_alkanesulfonate_uptake_desulfonationDRAFTABSTRACTMetabolic Pathwaymodules/bacterial_alkanesulfonate_uptake_desulfonation.yaml
alkanesulfonate catabolic processGO:0046306
PMID:10781557
The ssu locus plays a key role in organosulfur metabolism in Pseudomonas putida S-313
Pseudomonas genetics identifies an SsuABC transporter and SsuED reduced-flavin monooxygenase in one organosulfur-utilization locus.
an ATP-binding cassette-type transporter (ssuABC), a two-component reduced flavin mononucleotide-dependent monooxygenase (ssuED)
PMID:10480865
Characterization of a two-component alkanesulfonate monooxygenase from Escherichia coli
Purified SsuE supplies FMNH2 to SsuD, which oxygenolyzes a broad range of alkanesulfonates to sulfite and corresponding aldehydes.
SsuE is the FMN reducing enzyme providing SsuD with FMNH(2).
PMID:10781534
Deletion analysis of the Escherichia coli taurine and alkanesulfonate transport systems
Deletion and complementation distinguish the SsuABC alkanesulfonate importer from the parallel TauABC taurine importer.
the individual components of the two transport systems were not functionally exchangeable
file:projects/P_PUTIDA/deep-research/PSEPK__taurine_uptake_and_desulfonation__ppu00430-deep-research-openscientist.md
OpenScientist PSEPK taurine-pathway satisfiability review
The species-aware neighboring-pathway review identifies the KT2440 ssuEADCB locus as a parallel alkanesulfonate system and keeps it separate from TauABC/TauD taurine uptake and desulfonation.
file:modules/bacterial_alkanesulfonate_uptake_desulfonation-deep-research-openscientist.md
OpenScientist research for bacterial alkanesulfonate uptake and desulfonation
The generic review supports the transport-plus-reduced-flavin desulfonation boundary and separation from TauD and downstream sulfite assimilation. Its universal-SsuE and direct-channeling language was not promoted beyond what the primary evidence establishes.
UniProtKB:Q88R96
Pseudomonas putida KT2440 SsuA
Q88R96 is the exact periplasmic aliphatic-sulfonate-binding exemplar.
UniProtKB:Q88R93
Pseudomonas putida KT2440 SsuB
Q88R93 is the exact ATPase exemplar for the SsuABC importer.
UniProtKB:Q88R94
Pseudomonas putida KT2440 SsuC
Q88R94 is the exact membrane permease exemplar for the SsuABC importer.
UniProtKB:Q88R97
Pseudomonas putida KT2440 SsuE
Q88R97 is the exact NADPH-dependent FMN-reductase exemplar.
UniProtKB:Q88R95
Pseudomonas putida KT2440 SsuD
Q88R95 is the exact alkanesulfonate-monooxygenase exemplar.
UniProtKB:P75853
Escherichia coli K-12 SsuA
P75853 is a reviewed SsuA-family binding-protein exemplar.
UniProtKB:P0AAI1
Escherichia coli K-12 SsuB
P0AAI1 is a reviewed SsuB ATPase exemplar.
UniProtKB:P75851
Escherichia coli K-12 SsuC
P75851 is a reviewed SsuC permease exemplar.
UniProtKB:P80644
Escherichia coli K-12 SsuE
P80644 is a biochemically characterized SsuE reductase exemplar.
UniProtKB:P80645
Escherichia coli K-12 SsuD
P80645 is a biochemically characterized SsuD oxygenase exemplar.

The broad substrate-binding and permease PANTHER families contain transporters with other substrates, so the SsuABC complex is constrained by the exact alkanesulfonate transporter function and grounded by verified Pseudomonas and E. coli exemplars. SsuE is the canonical reduced-FMN supplier but is optional at this reusable boundary because Pseudomonas S-313 genetics demonstrates alternative reductase coverage for aliphatic sulfonate growth.

5Nodes
4Parts
0Variant Sets
0Variants
3Annotons
2Connections

Derived QC

Recommended-field compliance

55.6% 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 deep research

✓ present

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

Leaf nodes lacking representative members

✓ representative grounding skipped for abstract module.

Template conformance

✓ every declared conforms_to bundle matches its template motif.

Gene-review completeness (5/10 grounded genes reviewed)

5 complete review(s) · 2 with deep research · 5 missing review · 3 reviewed but lacking deep research

Gene Review Complete Deep research
SsuB (Escherichia coli K-12) P0AAI1 ✗ — —
SsuC (Escherichia coli K-12) P75851 ✗ — —
SsuA (Escherichia coli K-12) P75853 ✗ — —
SsuE (Escherichia coli K-12) P80644 ✗ — —
SsuD (Escherichia coli K-12) P80645 ✗ — —
ssuA Q88R96 ✓ ✓ ✗
ssuB Q88R93 ✓ ✓ ✓
ssuC Q88R94 ✓ ✓ ✗
ssuD Q88R95 ✓ ✓ ✓
ssuE Q88R97 ✓ ✓ ✗

Details

Context
bacteriaNCBITaxon:2
Bacterial alkanesulfonate uptake and FMN-dependent desulfonationMetabolic Pathwaybacterial_alkanesulfonate_uptake_desulfonation
alkanesulfonate catabolic processGO:0046306
Context
bacteriaNCBITaxon:2

Connections

ssuabc_import -> ssud_desulfonation Provides Input For
SsuABC supplies cytoplasmic alkanesulfonate to SsuD.
Part 1: alkanesulfonate import
SsuABC alkanesulfonate importTransport Stepssuabc_import

Annotons

SsuABC alkanesulfonate transporter
ssuabc_transport_activity
Participant: Protein Complex: bacterial SsuABC alkanesulfonate importer
Protein Complex:
bacterial SsuABC alkanesulfonate importerGO:0055052
Active units:
SsuA substrate-binding subunit
Participant: Family: SsuA aliphatic-sulfonate-binding family
Family:
SsuA aliphatic-sulfonate-binding familyPANTHER:PTHR30024:SF42
Representative Members: SsuA (Pseudomonas putida KT2440)UniProtKB:Q88R96 SsuA (Escherichia coli K-12)UniProtKB:P75853
Role: Captures aliphatic sulfonates in the periplasm.
SsuB ATPase subunit
Participant: Family: SsuB alkanesulfonate-import ATPase family
Family:
SsuB alkanesulfonate-import ATPase familyPANTHER:PTHR42788:SF17
Representative Members: SsuB (Pseudomonas putida KT2440)UniProtKB:Q88R93 SsuB (Escherichia coli K-12)UniProtKB:P0AAI1
Role: Couples ATP hydrolysis to alkanesulfonate import.
SsuC permease subunit
Participant: Family: SsuC alkanesulfonate permease family
Family:
SsuC alkanesulfonate permease familyPANTHER:PTHR30151:SF38
Representative Members: SsuC (Pseudomonas putida KT2440)UniProtKB:Q88R94 SsuC (Escherichia coli K-12)UniProtKB:P75851
Role: Forms the membrane translocation path.
Required Function:
ABC-type alkanesulfonate transporter transporter activityGO:0042959

Function

ABC-type alkanesulfonate transporter transporter activityGO:0042959
Substrates: extracellular alkanesulfonate ATP
Products: cytoplasmic alkanesulfonate ADP phosphate

Processes

alkanesulfonate transmembrane transportGO:0042918
Part 2: reduced-flavin oxidative desulfonation
SsuE/SsuD reduced-flavin desulfonationMetabolic Pathwayssued_desulfonation

A two-step reduced-flavin system in which an FMN reductase supplies diffusible FMNH2 and SsuD uses that cosubstrate with oxygen to cleave the carbon-sulfur bond of an alkanesulfonate.

Connections

ssue_fmn_reduction -> ssud_desulfonation Provides Input For
SsuE supplies reduced FMN to the SsuD monooxygenase cycle.
Part 1: canonical reduced FMN supply (optional)
SsuE NADPH-dependent FMN reductionReactionssue_fmn_reduction

SsuE is the canonical reductase partner, but another flavin reductase can provide the required FMNH2 in some bacteria.

Annotons

SsuE FMN reductase activity
ssue_activity
Participant: Family: SsuE FMN reductase family
Family:
SsuE FMN reductase familyPANTHER:PTHR43408:SF1
Representative Members: SsuE (Pseudomonas putida KT2440)UniProtKB:Q88R97 SsuE (Escherichia coli K-12)UniProtKB:P80644
Required Function:
FMN reductase (NADPH) activityGO:0052873

Function

FMN reductase (NADPH) activityGO:0052873
Substrates: FMN NADPH
Products: reduced FMN NADP+
Part 2: oxidative desulfonation
SsuD alkanesulfonate monooxygenationReactionssud_desulfonation

Annotons

SsuD alkanesulfonate monooxygenase activity
ssud_activity
Participant: Family: SsuD alkanesulfonate monooxygenase subfamily
Family:
SsuD alkanesulfonate monooxygenase subfamilyPANTHER:PTHR42847:SF4
Representative Members: SsuD (Pseudomonas putida KT2440)UniProtKB:Q88R95 SsuD (Escherichia coli K-12)UniProtKB:P80645
Required Function:
alkanesulfonate monooxygenase activityGO:0008726

Function

alkanesulfonate monooxygenase activityGO:0008726
Substrates: alkanesulfonate reduced FMN oxygen
Products: corresponding aldehyde sulfite FMN water