katA (PA4236) review notes

Literature search (2026-11-05)

No existing katA folder was present in genes/PSEAE, so this is a new review. No
deep-research provider was available, and the PubMed MCP and Europe PMC search
endpoints failed during this session. Sources read: PMID:10368148 (full text,
Ma et al. 1999) and PMID:24663218 (full text, Su et al. 2014), both cited by
UniProt and fetched with the repository tooling.

Findings

KatA purified to homogeneity (FRD2 katB background, and as a His-tagged
recombinant protein); apparent Km for H2O2 44.7 mM; katA complements a
catalase-deficient E. coli PMID:10368148.
katA mutants: no detectable catalase activity; hypersusceptible to H2O2
PMID:10368148.
BfrA is needed for full KatA activity, probably as a heme-iron source
PMID:10368148.
Ferric heme binds NO directly (Kd about 6 microM); katA mutants are more
sensitive to anaerobic NO PMID:24663218. Added as
NEW GO:0070026 nitric oxide binding (IDA).

PseudoCAP IBA-seed assessment

PTN node	node term	n_seeds	leaf IBAs	seed annotation (term, evidence, PMID)	other seeds	IBD stands without this seed?	verdict	rationale
PTN000157250	GO:0004096 catalase activity	25	283 (109 taxa)	GO:0004096, IDA, PMID:10368148 (PseudoCAP)	24 others, including human CAT P04040, yeast CTA1 and CTT1, Drosophila Cat, Arabidopsis AT4G35090, MGI:88271, RGD:2279	Yes	SOUND	Purified-enzyme kinetics, complementation and loss of activity in the mutant. Node term fits the monofunctional heme catalase clade.

No GO_CENTRAL defect.