wbpX (PA5449, G3XCU3) review notes

No deep-research provider was available. Sources: UniProt record (TrEMBL), cached
PMID:9680202 (abstract only, no PMC full text). PubMed and Europe PMC searches failed
on 2026-11-05 (server errors), so no later literature could be retrieved.

Function

WbpX is one of three alpha-D-rhamnosyltransferases that assemble the A-band (common
polysaccharide antigen) D-rhamnan O-polysaccharide
PMID:9680202.
Proposed role: alpha1-2 rhamnosyl transfer, processive and alternating with WbpY
PMID:9680202;
PMID:9680202.
Mutant phenotype: no A-band LPS, B-band unaffected
PMID:9680202.
Domain: glycosyltransferase family 1 (Pfam PF00534, InterPro IPR001296), CDD GT4_MtfB-like.

The linkage assignments in the paper are inferences from repeat-unit structure and gene
order; the abstract reports genetics (mutants, Western blot) rather than enzyme assays.

PseudoCAP IBA-seed assessment

PTN node	node term	n_seeds	leaf IBAs	seed annotation (term, evidence, PMID)	verdict	rationale	other seeds	IBD stands without this seed?
PTN005302544	GO:0016757 glycosyltransferase activity	2	60 (22 taxa)	GO:0016757 glycosyltransferase activity, IMP, PMID:9680202 (PseudoCAP)	SOUND	Generic GT activity for a GT1-domain protein whose mutant cannot make the A-band rhamnan. The specific linkage is inferred, but the node term is the generic one, which the domain plus mutant data support.	WbpY Q9HTB9 (same paper, same kind of evidence)	Yes in substance; WbpY's seed rests on the same paper and the same genetic logic, and the GT1 domain supports the generic term for the whole clade. No GO_CENTRAL defect.

Defects recorded: PSEUDOCAP 0; GO_CENTRAL 0.