fabA (PA1610, O33877) review notes

No deep-research provider was available. Sources: UniProt record (O33877),
cached PMID:9286984 (abstract only; PMC full text body not returned by the
PubMed MCP). fabB (PA1609) was reviewed earlier and shares the biology.

Function

Dual dehydratase/isomerase of type II FAS; the isomerase introduces cis
unsaturation [file:PSEAE/fabA/fabA-uniprot.txt "Necessary for the introduction of
cis unsaturation into fatty acids. Catalyzes the dehydration of
(3R)-3-hydroxydecanoyl-ACP to E-(2)-decenoyl-ACP and then its isomerization to
Z-(3)-decenoyl-ACP"].
fabA/fabB cloned; chromosomal fabA mutants auxotrophic for UFA; fabAB operon
[PMID:9286984 "the mutants were auxotrophic for unsaturated fatty acids";
"fabA and fabB are cotranscribed"].

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?
PTN008624492	GO:0006633 fatty acid biosynthetic process	3	124 (73 taxa)	GO:0006636 unsaturated fatty acid biosynthetic process, IMP, PMID:9286984 (PseudoCAP)	SOUND	The seed is the UFA auxotrophy of fabA mutants, but for fabA phenotype and catalysis coincide: its isomerase makes the cis-3-decenoyl-ACP intermediate, the committed step of UFA synthesis. The node term is the parent GO:0006633, right for a FabA/FabZ dehydratase clade; the seed's GO:0006636 is a descendant.	E. coli FabA P0A6Q3, E. coli FabZ P0A6Q6 (and Arabidopsis AT2G22230 for the GO:0019171 IBD)	Yes; E. coli FabA and FabZ carry strong experimental support. No GO_CENTRAL defect.

Same node also carries the GO:0019171 (3R)-hydroxyacyl-ACP dehydratase activity
IBD (P0A6Q3, P0A6Q6, AT2G22230) - sound, family-defining activity. This mirrors
the reviewed fabB (PTN000918584): a wet-lab auxotrophy that coincides with the
enzyme's own committed catalytic step, not an indirect phenotype.

PseudoCAP defects from this gene: none.