moaC encodes cyclic pyranopterin monophosphate synthase, the MoaC enzyme that converts a cyclic GTP-derived precursor to cPMP during molybdopterin cofactor biosynthesis.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0006777 Mo-molybdopterin cofactor biosynthetic process | IEA GO_REF:0000120 | ACCEPT | Summary: MoaC should retain the Mo-molybdopterin cofactor biosynthetic process annotation. Reason: UniProt places MoaC in molybdopterin biosynthesis and describes the cPMP-forming reaction. Supporting Evidence: file:PSEPK/moaC/moaC-uniprot.txt PATHWAY: Cofactor biosynthesis; molybdopterin biosynthesis file:PSEPK/moaC/moaC-goa.tsv GO:0006777 Mo-molybdopterin cofactor biosynthetic process file:PSEPK/moaC/moaC-deep-research-falcon.md Across bacteria and eukaryotes, Moco biosynthesis is commonly described as a sequence of conserved steps. A mechanistic perspective summarizes three conserved stages: (1) rearrangement of **GTP** into **cPMP**, (2) sulfur insertion to form **MPT**, and (3) insertion of molybdate (Mo) to produce Moco. file:PSEPK/moaC/moaC-deep-research-falcon.md the conserved role of MoaC in cPMP synthesis implies it is upstream of all KT2440 Moco-dependent enzymes |
| GO:0061799 cyclic pyranopterin monophosphate synthase activity | IEA GO_REF:0000120 | ACCEPT | Summary: Cyclic pyranopterin monophosphate synthase activity is the correct core molecular function for MoaC. Reason: UniProt assigns EC 4.6.1.17 and the Rhea reaction producing cyclic pyranopterin phosphate. Supporting Evidence: file:PSEPK/moaC/moaC-uniprot.txt Cyclic pyranopterin monophosphate synthase file:PSEPK/moaC/moaC-uniprot.txt EC=4.6.1.17 file:PSEPK/moaC/moaC-goa.tsv GO:0061799 cyclic pyranopterin monophosphate synthase activity file:PSEPK/moaC/moaC-deep-research-falcon.md MoaC catalyzes the conversion of the MoaA product, 3′,8-cH2GTP, into cyclic pyranopterin monophosphate (cPMP). file:PSEPK/moaC/moaC-deep-research-falcon.md This establishes MoaC’s **substrate specificity** as being directed to **3′,8-cH2GTP** (not GTP directly) and its **product** as cPMP, the first stable committed intermediate in Moco biosynthesis. file:PSEPK/moaC/moaC-deep-research-openscientist.md | Catalytic reaction (UniProt) | 3′,8-cH₂GTP = cyclic pyranopterin phosphate + diphosphate | |
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Download this section (compressed HTML)Q: Does KT2440 MoaC function independently as a homohexamer in vivo or require stable association with upstream MoaA pathway components?
Experiment: Assay cPMP production with purified MoaC and pathway precursor, and compare molybdoenzyme activity in wild-type and moaC knockout strains.
Type: enzyme assay and molybdoenzyme activity profiling
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