hemC

Existing Annotations Review

GO Term	Evidence	Action	Reason
GO:0004418 hydroxymethylbilane synthase activity	IEA GO_REF:0000120	ACCEPT	Summary: This is the specific core catalytic function of HemC. Reason: UniProt assigns EC 2.5.1.61 and describes tetrapolymerization of porphobilinogen into hydroxymethylbilane. Supporting Evidence: file:PSEPK/hemC/hemC-uniprot.txt Tetrapolymerization of the monopyrrole PBG into the
GO:0005737 cytoplasm	IEA GO_REF:0000120	ACCEPT	Summary: Cytoplasmic localization is consistent with this soluble bacterial enzyme. Reason: HemC lacks membrane or export features, and the current UniProt cross-reference retains a cytoplasmic assignment. Supporting Evidence: file:PSEPK/hemC/hemC-uniprot.txt GO; GO:0005737; C:cytoplasm;
GO:0006783 heme biosynthetic process	IEA GO_REF:0000120	ACCEPT	Summary: HemC is an obligatory middle enzyme in the protoporphyrin route to heme b. Reason: The HemC reaction generates the linear tetrapyrrole precursor required for uroporphyrinogen III and all downstream heme-b intermediates. Supporting Evidence: file:PSEPK/hemC/hemC-uniprot.txt PATHWAY: Porphyrin-containing compound metabolism; protoporphyrin-IX
GO:0033014 tetrapyrrole biosynthetic process	IEA GO_REF:0000002	MODIFY	Summary: The annotation is true but can be made more specific to the immediate product route. Reason: HemC directly builds hydroxymethylbilane for conversion to uroporphyrinogen III, so GO:0006780 is more informative than the broad tetrapyrrole parent. Proposed replacements: uroporphyrinogen III biosynthetic process Supporting Evidence: file:PSEPK/hemC/hemC-uniprot.txt Tetrapolymerization of the monopyrrole PBG into the