PA4400 (Q9HW06) notes

Identity: MutT, fused to a TenI-like domain

TrEMBL, unreviewed, no gene name in UniProt. N-terminal Nudix hydrolase
domain (1-128, Nudix box 38-59; NCBIfam TIGR00586 mutt; IPR003561
Mutator_MutT) fused to a C-terminal thiamine-phosphate synthase-like TenI
domain (PF02581 TMP-TENI; NCBIfam NF006530 PRK08999).
[file:PSEAE/PA4400/PA4400-uniprot.txt "Mutator_MutT"]
This is the mutT characterised by Oliver et al. 2002, whose abstract
describes the same two-part architecture:
PMID:12445642

Literature

Oliver, Sanchez and Blazquez 2002, PMID:12445642 (abstract only; no PMC).
- Cloned PAO1 mutT, mutM and mutY complement the mutator phenotype of the
corresponding E. coli mutants:
PMID:12445642
PMID:12445642
- The abstract describes heterologous complementation of mutation frequency.
Whether a direct 8-oxo-dGTPase assay was done cannot be seen. The "necessary
and sufficient" statement may come from complementation with truncations.

Later work (not cached here) links P. aeruginosa GO-system defects (mutT,
mutY) to hypermutability in cystic fibrosis isolates; not needed for the
annotation calls.

Comparator check for "DNA repair" on MutT

E. coli MutT (P08337) carries GO:0006281 DNA repair as EcoCyc EXP
(acts_upstream_of_or_within, PMID:7739614) and UniProt IC (PMID:10373420);
human NUDT1 carries DNA repair (IC) and DNA protection (GO:0042262). GO
practice is to annotate MutT-type 8-oxo-dGTPases, which prevent
incorporation of oxidised guanine, to DNA repair. The PseudoCAP term follows
that convention and is accepted.

PseudoCAP IBA-seed assessment

Seeds from .cache/paint/IBD.gaf; P08337 annotations from QuickGO 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?
PTN000755027	GO:0006281 DNA repair	2	27 (22 taxa)	GO:0006281, IDA, PMID:12445642	SOUND	Complementation of the E. coli mutT mutator phenotype shows the antimutator (GO system) function; DNA repair is the GO convention for MutT. The evidence is heterologous complementation (IGI), not IDA: PSEUDOCAP WRONG_EVIDENCE_CODE, PROBABLE (abstract states the method). Term suits the MutT clade.	E. coli MutT P08337 (EXP PMID:7739614, EcoCyc; IC PMID:10373420, UniProt)	Yes

The other IBDs at this node (8-oxo-dGTP, 8-oxo-GTP pyrophosphatase; 8-oxo-dGDP,
8-oxo-GDP phosphatase) rest on P08337 only, with direct IDA data; PA4400 is
not a seed. No GO_CENTRAL defect.

Review decisions

ACCEPT: DNA repair (IBA, IDA with evidence-code defect, IEA);
8-oxo-dGTP pyrophosphatase activity (IBA, IEA).
KEEP_AS_NON_CORE: 8-oxo-GTP pyrophosphatase (IBA, IEA), 8-oxo-dGDP and
8-oxo-GDP phosphatase (IBA). Shown for E. coli MutT; secondary to the
dGTP-pool activity, not tested for PA4400.
MODIFY: metal ion binding -> magnesium ion binding.
TOO_GENERAL: hydrolase activity (IDA, IEA); GO:0035539 accepted.
The TenI-like C-terminal domain has no GO row and no experimental data; a
thiamine-related activity is not proposed.