PA3271 (mxtR, Q9HYX0) notes

Literature

No deep-research provider was available. PubMed E-utilities returned HTTP 500
on 2026-11-05. The cached publications were searched for MxtR/PA3271, and only
PMID:22168309 (abstract only) was found.

MxtR is an orphan sensor kinase that modulates AQ production PMID:22168309.
The mutant induces MexT and MexEF-OprN, which delays AQ biosynthesis gene
expression.
In vitro autophosphorylation is inhibited by ubiquinone PMID:22168309.
Domain content (UniProt InterPro/Pfam/SMART): SSF symporter-family 13-TM
domain, PAS-like, HisKA (His808), HATPase_c, REC (Asp1090). There is no HPt
domain.

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?
PTN001976860	GO:0000155 phosphorelay sensor kinase activity	3	330 (86 taxa)	GO:0000155, IDA, PMID:22168309 (PseudoCAP)	SOUND	The abstract states outright that MxtR autophosphorylation was assayed in vitro and inhibited by ubiquinone. That is direct kinase evidence with a sensory input; HisKA/HATPase/REC architecture is intact.	M. tuberculosis SenX3 P9WGK5 (IDA); P. aeruginosa RpfC PA1611 Q9I3B1 (IDA, PMID:16182517; see genes/PSEAE/PA1611)	Yes. SenX3 alone grounds the node, and PA1611 is also sound. No PSEUDOCAP or GO_CENTRAL defect for this term.

Node-level issue on another term: PTN001976860 also carries an IBD for
GO:0009927 histidine phosphotransfer kinase activity (seeds RcsD P39838, with an
HPt domain, and SGD:S000001409). It reaches MxtR, which has no HPt domain.
The IBA row is REMOVE here. The single GO_CENTRAL defect (PROBABLE) is
recorded on PA1611 (genes/PSEAE/PA1611), which shares the node and the
problem; this review cross-references it and does not duplicate it.

Other decisions

GO:0022857 and GO:0055085 (SSF-domain transport): MARK_AS_OVER_ANNOTATED.
GO:1900376 regulation of secondary metabolite biosynthesis (IMP):
KEEP_AS_NON_CORE, an indirect effect through MexT.
GO:0004673, GO:0007165, GO:0016020, GO:0016301, GO:0016740, GO:0016772:
TOO_GENERAL.