F5HN73 · CPAD_ASPOZ
- ProteinCyclo-acetoacetyl-L-tryptophan dimethylallyltransferase cpaD
- GenecpaD
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids437 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score3/5
Function
function
Cyclo-acetoacetyl-L-tryptophan dimethylallyltransferase; part of the gene cluster that mediates the biosynthesis of the fungal neurotoxin cyclopiazonic acid (CPA), a nanomolar inhibitor of Ca2+-ATPase with a unique pentacyclic indole tetramic acid scaffold (PubMed:21608094).
The hybrid two module polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) cpaS incorporates acetyl-CoA, malonyl-CoA, and tryptophan (Trp) and utilizes a C-terminal redox-incompetent reductase domain to make and release the tryptophan tetramic acid, cyclo-acetoacetyl-L-tryptophan (c-AATrp), as the first intermediate in the pathway. CpaS catalyzes a Dieckmann-type cyclization on the N-acetoacetyl-Trp intermediate bound in thioester linkage to the phosphopantetheinyl arm of the T domain to form and release c-AATrp (PubMed:19663400, PubMed:21608094).
CpaD then regiospecifically dimethylallylates c-AATrp to form beta-cyclopiazonic acid. CpaD discriminates against free Trp but accepts tryptophan-containing thiohydantoins, diketopiperazines, and linear peptides as substrates for C4-prenylation and also acts as a regiospecific O-dimethylallyltransferase (DMAT) on a tyrosine-derived tetramic acid (PubMed:19877600, PubMed:21608094).
The beta-cyclopiazonate dehydrogenase cpaO then carries out the dehydrogenation of beta-CPA to yield an unstable enimine product, which is captured by intramolecular cyclization to create the pentacyclic fused scaffold of alpha-cyclopiazonate (PubMed:21608094).
Finally, the cytochrome P450 monooxygenase cpaH mediates the conversion of CPA into the less toxic 2-oxocyclopiazonic acid, the end product of the CPA pathway in A.oryza (PubMed:21608094).
The hybrid two module polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) cpaS incorporates acetyl-CoA, malonyl-CoA, and tryptophan (Trp) and utilizes a C-terminal redox-incompetent reductase domain to make and release the tryptophan tetramic acid, cyclo-acetoacetyl-L-tryptophan (c-AATrp), as the first intermediate in the pathway. CpaS catalyzes a Dieckmann-type cyclization on the N-acetoacetyl-Trp intermediate bound in thioester linkage to the phosphopantetheinyl arm of the T domain to form and release c-AATrp (PubMed:19663400, PubMed:21608094).
CpaD then regiospecifically dimethylallylates c-AATrp to form beta-cyclopiazonic acid. CpaD discriminates against free Trp but accepts tryptophan-containing thiohydantoins, diketopiperazines, and linear peptides as substrates for C4-prenylation and also acts as a regiospecific O-dimethylallyltransferase (DMAT) on a tyrosine-derived tetramic acid (PubMed:19877600, PubMed:21608094).
The beta-cyclopiazonate dehydrogenase cpaO then carries out the dehydrogenation of beta-CPA to yield an unstable enimine product, which is captured by intramolecular cyclization to create the pentacyclic fused scaffold of alpha-cyclopiazonate (PubMed:21608094).
Finally, the cytochrome P450 monooxygenase cpaH mediates the conversion of CPA into the less toxic 2-oxocyclopiazonic acid, the end product of the CPA pathway in A.oryza (PubMed:21608094).
Catalytic activity
- cyclo-acetoacetyl-L-tryptophan + dimethylallyl diphosphate = beta-cyclopiazonate + diphosphateThis reaction proceeds in the forward direction.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
109 μM | L-c-AATrp | |||||
3829 μM | D-c-AATrp |
Pathway
Secondary metabolite biosynthesis.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 84-85 | L-tryptophan (UniProtKB | ChEBI) | ||||
Sequence: HL | ||||||
Binding site | 93 | L-tryptophan (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Binding site | 104 | substrate | ||||
Sequence: R | ||||||
Binding site | 191 | substrate | ||||
Sequence: K | ||||||
Binding site | 193 | substrate | ||||
Sequence: Y | ||||||
Binding site | 195 | L-tryptophan (UniProtKB | ChEBI) | ||||
Sequence: Y | ||||||
Binding site | 258 | substrate | ||||
Sequence: R | ||||||
Binding site | 260 | substrate | ||||
Sequence: K | ||||||
Binding site | 262 | substrate | ||||
Sequence: Y | ||||||
Binding site | 344 | substrate | ||||
Sequence: Q | ||||||
Binding site | 346 | substrate | ||||
Sequence: Y | ||||||
Binding site | 410 | substrate | ||||
Sequence: Y | ||||||
Binding site | 414 | substrate | ||||
Sequence: Y |
GO annotations
Aspect | Term | |
---|---|---|
Molecular Function | transferase activity, transferring alkyl or aryl (other than methyl) groups | |
Biological Process | alkaloid metabolic process |
Keywords
- Molecular function
- Biological process
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameCyclo-acetoacetyl-L-tryptophan dimethylallyltransferase cpaD
- EC number
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageEukaryota > Fungi > Dikarya > Ascomycota > Pezizomycotina > Eurotiomycetes > Eurotiomycetidae > Eurotiales > Aspergillaceae > Aspergillus > Aspergillus subgen. Circumdati
Accessions
- Primary accessionF5HN73
Organism-specific databases
Phenotypes & Variants
Disruption phenotype
Impairs the production of cyclopiazonic acid and of its biosynthetic intermediate beta-cyclopiazonic acid, but accumulates the intermediate cyclo-acetoacetyl-L-tryptophan.
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000445386 | 1-437 | Cyclo-acetoacetyl-L-tryptophan dimethylallyltransferase cpaD | |||
Sequence: MEISKKAATLLPKPFYVLSQALNLSNKDHTKWWYSTAPMFATMMAGAGYDVHAQYKFLCIHREVIIPALGPYPEKGQPMHWKSHLTRFGLPFELSFNYSKSLLRFAFEPLGSLTGTKDDPFNTQAIRPVLQDLKAMVPGLDLEWFDHFTKALVVSEEEARTLLDRDIEIPVFKTQNKLAADLEPSGDIVLKTYIYPRIKSIATGTPKERLMFDAIKAADKFGKVATPLAILEEFIAERAPTLLGHFLSCDLVKPSESRIKVYCMERQLDLASIEGIWTLNGRRNDPETLDGLDALRELWQLLPVTEGLCPLPNCFYEPGTSPQEQLPFIINFTLSPKSALPEPQIYFPAFGQNDKTIAEGLATFFESRGWGGLAKSYPADLASYYPDVDLQTANHLQAWISFSYKGKKPYMSVYLHTFEAFSAAAQEVAMCHDGHNP |
Structure
Sequence
- Sequence statusComplete
- Length437
- Mass (Da)49,186
- Last updated2011-07-27 v1
- Checksum67CAB188CDDDDDA0