PA3345 / HptB (Q9HYQ0) review notes

Literature

Search (Europe PMC REST, 2026-11-05: TITLE:HptB AND aeruginosa,
TITLE:"histidine-containing phosphotransfer" AND aeruginosa) returned PMIDs 16182517,
18256026, 20398205, 22128156, 27792789 (and its correction 27902688). PMID:31019225 was
added for the HsbR-RpoS link.

  1. Lin et al. 2006 PMID:16182517, abstract only. PA1611 signals through HptB (PA3345)
    to PA3346 PMID:16182517. Phenotypes of an hptB deletion implicate it in flagellar activity, chemotaxis,
    twitching and biofilm formation; the abstract does not give the signs.
  2. Hsu et al. 2008 PMID:18256026, abstract only. In vitro phosphorelay profiling: four
    sensors (PA1611, PA1976, PA2824, RetS) transfer phosphoryl groups to HptB, and from HptB
    to PA3346 (HsbR) PMID:18256026. Bacterial two-hybrid interactions with each sensor.
  3. Bordi et al. 2010 PMID:20398205, full text cached. hptB deletion is hyperbiofilm
    (pel-dependent, via GacA and rsmY), complemented by hptB in trans PMID:20398205.
  4. Bhuwan et al. 2012 PMID:22128156, abstract only. hptB mutant is non-swarming; HsbR
    (PA3346) kinase domain phosphorylates HsbA (PA3347), which partner-switches with FlgM.
  5. Valentini et al. 2016 PMID:27792789, full text cached. hptB mutant: more EPS,
    more attachment and twitching, less swimming and swarming.
  6. Bouillet et al. 2019 PMID:31019225, full text cached. HsbR is an anti-sigma factor
    for RpoS; RpoS acts downstream of HptB in biofilm control.

Sign summary: HptB negatively regulates biofilm formation and twitching, positively
regulates swimming and swarming. GO:2000145 regulation of cell motility (unsigned)
therefore fits the mixed-sign motility evidence.

UniProt Q9HYQ0: 116 aa, HPt domain 18-116 (PROSITE PS50894), phosphohistidine His57
(ProRule), PANTHER PTHR28242 (YPD1), crystal structure PDB 7C1I.

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?
PTN002000688 GO:0009927 histidine phosphotransfer kinase activity 9 462 (57 taxa) GO:0009927, IDA, PMID:16182517 (PseudoCAP) SOUND Abstract states that phosphoryl transfer from PA1611 to PA3346 goes through HptB; the follow-up (PMID:18256026, same group) shows in vitro transfer from four sensors to HptB and on to PA3346. HPt domain with conserved His57. Abstract-only reading, no defect claimed. Arabidopsis AHP1/2/3/5/AHP4 (AT3G21510, AT3G29350, AT1G03430, AT5G39340, AT3G16360), S. pombe Mpr1 (SPBC725.02), A. nidulans YpdA (Q5BBS5), Dictyostelium RdeA (DDB_G0282923) Yes; the eukaryotic HPt seeds (yeast and plant Ypd1/AHP proteins) have strong experimental support. The term defines HPt proteins and suits the clade. No GO_CENTRAL defect.

Consistency: PA3343 (HsbD) review describes HsbD as linking c-di-GMP signalling to the
HptB pathway; this review agrees (HptB → HsbR → HsbA → HsbD/FlgM, and HsbR → RpoS).
The rpoS review in this batch uses the same PMID:31019225 evidence for the RpoS-HsbR
sigma-factor antagonist complex.

Annotation decisions