wbpA (PA3159, G3XD94) notes

Sources read on 2026-11-05: UniProt G3XD94 (UGND_PSEAE), the GOA file, cached abstracts
of PMID:15226302, PMID:10930727, PMID:8939432 and the cached full text of PMID:18621892.
No deep-research provider file (no keys). Related reviews: genes/PSEAE/wbpI (shares
PMID:10930727), wbpD, wbpE.

Biology

WbpA is the first enzyme of the five-step WbpA-WbpB-WbpE-WbpD-WbpI pathway to
UDP-D-ManNAc3NAcA, a precursor of the serotype O5 B-band O antigen
PMID:18621892.
Purified His-WbpA is a UDP-GlcNAc 6-dehydrogenase (EC 1.1.1.136) using NAD+; product
UDP-GlcNAcA confirmed by NMR; requires NH4+ or K+; trimer in solution
PMID:15226302.
wbpA knockout loses B-band LPS
PMID:10930727;
restored by His-WbpA in trans (PMID:18621892 full text,
"The wbpA knockout of P. aeruginosa PAO1 is devoid of B-band O antigen but still produces A-band O antigen in a variety of lengths.").
In PMID:18621892 the enzymes assayed by capillary electrophoresis were the B. pertussis
WbpO homologs, not WbpA; NADH was detected as a product of those reactions. WbpA itself
appears only in knockout and complementation experiments in that paper.
Sequence check: the UniProt TRANSMEM 13-32 (ECO:0000255, a prediction) covers
SRQALIGIVGLGYVGLPLML, which contains the GxGxxG dinucleotide-binding motif of the
Rossmann fold (G22-L-G-Y-V-G27) at the N-terminus of the UDP-glucose/GDP-mannose
dehydrogenase family. This is the NAD-binding beta-alpha-beta unit, not a membrane
anchor; the enzyme was purified and characterised as a soluble oligomer
(PMID:15226302).

Annotation judgements

GO:0047004 (EXP, IEA): ACCEPT, core MF.
GO:0003954 NADH dehydrogenase activity (PseudoCAP EXP, PMID:18621892): REMOVE. NADH
dehydrogenase activity is NADH oxidation (NADH + acceptor -> NAD+); WbpA reduces NAD+
to NADH. In the cited paper the activity assay was on B. pertussis WbpO, not WbpA.
The correct term (GO:0047004) is already annotated from PMID:15226302. CONFIRMED
(full text read).
GO:0016628 (CH-CH donors) InterPro2GO from IPR028359: wrong sub-class; the enzyme
oxidises the C6 alcohol (EC 1.1.1.x, CH-OH donors). REMOVE, INTERPRO defect.
GO:0016616 (CH-OH donors) and GO:0016491: TOO_GENERAL (entailed by GO:0047004).
GO:0000271: TOO_GENERAL (entailed by GO:0009243 O antigen biosynthetic process).
GO:0009243 (EXP, IEA): ACCEPT, core BP.
GO:0016020 membrane (IEA, UniProt SubCell from a predicted TM helix): REMOVE; the
predicted helix is the Rossmann GxGxxG motif.
GO:0051287 NAD binding: ACCEPT (NAD+ coenzyme, Rossmann motif).

PseudoCAP IBA-seed assessment

Other seeds' experimental support queried live in QuickGO on 2026-11-05.

PTN node	node term	n_seeds	leaf IBAs	seed annotation (term, evidence, PMID)	verdict	rationale	other seeds	IBD stands without this seed?
PTN000890018	GO:0016491 oxidoreductase activity	2	30 (25 taxa)	GO:0003954 NADH dehydrogenase activity, EXP, PMID:18621892 (PseudoCAP)	WRONG	Full text: WbpA was only knocked out and complemented in this paper; the assayed dehydrogenases were B. pertussis WbpO, and NADH is the product, not the substrate. PSEUDOCAP WRONG_TERM, CONFIRMED.	E. coli WecC P27829 (EcoCyc IDA GO:0089714 UDP-N-acetyl-D-mannosamine dehydrogenase activity, PMID:381306)	Yes; WecC alone supports it, and WbpA's own GO:0047004 seed is sound
PTN000890018	GO:0016491 oxidoreductase activity	2	30 (25 taxa)	GO:0047004, EXP, PMID:15226302 (PseudoCAP)	SOUND	Abstract: purified WbpA converts UDP-GlcNAc to UDP-GlcNAcA with NAD+, product confirmed by NMR, kinetics measured. (IDA would be the usual code; EXP is acceptable.)	as above	Yes
PTN000146785	GO:0000271 polysaccharide biosynthetic process	2	17 (15 taxa)	GO:0000271, IDA, PMID:15226302 (PseudoCAP)	SOUND	WbpA makes the first nucleotide-sugar precursor of B-band O antigen; it does a step of the pathway.	E. coli WecC P27829 (EcoCyc IMP GO:0009246 enterobacterial common antigen biosynthetic process, PMID:2166030; is_a GO:0000271)	Yes
PTN000146785	GO:0000271 polysaccharide biosynthetic process	2	17 (15 taxa)	GO:0009243 O antigen biosynthetic process, EXP, PMID:18621892 (PseudoCAP)	SOUND	Full text: wbpA knockout lacks B-band O antigen and His-WbpA in trans restores it (mutant evidence; IMP would be the usual code).	as above	Yes

Both node terms are broad and suit clades of nucleotide-sugar dehydrogenases feeding
ECA, capsule and O antigen. No GO_CENTRAL defect. Consistent with wbpI, where the
PTN001056041 polysaccharide-biosynthesis seed from PMID:10930727 was also judged SOUND.

Defects recorded: PSEUDOCAP WRONG_TERM on GO:0003954 (CONFIRMED); INTERPRO WRONG_TERM on
the IPR028359 -> GO:0016628 mapping (CONFIRMED); UNIPROT on the predicted TM segment
behind GO:0016020 (PROBABLE).