GSTF11

Summary: PAINT inference of glutathione transferase activity for the phi-class GST node PTN000136955, seeded by experimentally characterised Arabidopsis phi GSTs (GSTF9, GSTF10, GSTF2, GSTF6), maize and other GSTs.

Reason: GSTF11 is a canonical phi-class GST with the conserved thioredoxin-like N-terminal and GST C-terminal domains, and there is no evidence of loss of catalytic residues. Although recombinant GSTF11 has not been purified in soluble form [PMID:19174456], overexpression raised GST activity in planta [PMID:34961200], and the node placement is sound.

Summary: Electronic assignment of EC 2.5.1.18 based on the UniProt catalytic-activity annotation (by similarity to GSTF9).

Reason: Consistent with family membership and with the increased GST activity on overexpression [PMID:34961200].

Summary: Curator transfer of glutathione transferase activity from the paralog GSTF9 (O80852), which has direct enzymatic evidence.

Reason: GSTF9 is a close phi-class paralog; the transfer is appropriate for a conserved catalytic activity and agrees with the IBA.

Summary: PAINT inference that phi-class GSTs act in the cytoplasm.

Reason: GSTF11 lacks targeting signals and phi GSTs are soluble cytosolic enzymes; a cytosolic location matches the cytosolic glucosinolate core-pathway enzymes that act downstream (GGP1, SUR1).

Summary: Class-level statement from the Arabidopsis GST family survey that phi and tau GSTs are cytoplasmic; cached record is abstract-only.

Reason: Consistent with the IBA and the absence of targeting signals.

Summary: Mapping of UniProt subcellular location "Cytoplasm, cytosol" (curator inference).

Reason: Cytosol is the expected site of action of a soluble phi GST without targeting sequences.

Summary: Glutathione conjugation is the biochemical process performed by this GST.

Reason: The enzyme uses glutathione in conjugate formation. This term is as precise as the established general GST chemistry permits without asserting a fully reconstructed native glucosinolate-intermediate reaction; pathway genetics is discussed separately.

Summary: Richards et al. 1998 isolated an aluminium-induced GST cDNA clone identified by >98% identity to a previously published Arabidopsis GST (Kiyosue et al. 1993), and argued that Al induces oxidative-stress genes. The ozone (oxidative stress) response of the GST was cited from earlier work rather than tested for this clone.

Reason: The full text (cached) identifies the aluminium-induced GST clone only by its >98% identity to the GST published by Kiyosue et al. 1993. That paper (UniProt PubMed:8253194) described the dehydration-inducible phi GSTs ERD11 and ERD13; UniProt lists ERD11 as a synonym of GSTF6 (At1g02930) and ERD13 as a synonym of GSTF10 (P42761, At2g30870), not of GSTF11 (At3g03190). Richards et al. cite the Kiyosue "GST" in the singular and do not say which of the two clones they matched, but neither can be GSTF11. Global alignments of the UniProt sequences (GSTF11-bioinformatics/RESULTS.md) give 39.6% identity between GSTF11 and GSTF6/ERD11 and 42.7% between GSTF11 and GSTF10/ERD13, both incompatible with a >98%-identical cDNA. GSTF11 carries the historical alias "AtGSTF6", which collides with the current GSTF6/ERD11 symbol and is the most likely source of a locus mis-mapping. In addition, the treatment was aluminium; oxidative-stress inducibility of GST was cited from earlier ozone work rather than measured for this clone. Because the cached full text itself identifies a different gene and the response was not to oxidative stress, the annotation is removed for GSTF11. Stress inducibility of GSTF11 remains plausible on other evidence (e.g. PMID:34961200), but not from this paper.

Summary: A specific toxin-catabolic role is not resolved by the available evidence.

Reason: Model-substrate conjugation and GST-family membership do not by themselves establish physiological toxin catabolism. The original broad family study is abstract-only in the cache and its gene-specific claim could not be checked; retain uncertainty consistently for the TAS and propagated row rather than infer detoxification from family reputation.

Summary: A specific toxin-catabolic role is not resolved by the available evidence.

Reason: Model-substrate conjugation and GST-family membership do not by themselves establish physiological toxin catabolism. The original broad family study is abstract-only in the cache and its gene-specific claim could not be checked; retain uncertainty consistently for the TAS and propagated row rather than infer detoxification from family reputation.

Summary: PAINT inference of glutathione binding for phi GSTs (seeded by GSTF9/GSTF10 affinity data and others).

Reason: GSH binding at the conserved G-site is intrinsic to phi GST function, and GSTF11 retains the phi-class GST N-terminal domain.