| IED ID | IndEnz0010001448 |
| Enzyme Type ID | esterase001448 |
| Protein Name |
Versicolorin reductase stcU EC 1.3.1.- Sterigmatocystin biosynthesis cluster protein U |
| Gene Name | stcU verA AN7806 |
| Organism | Emericella nidulans (strain FGSC A4 / ATCC 38163 / CBS 112.46 / NRRL 194 / M139) (Aspergillus nidulans) |
| Taxonomic Lineage | cellular organisms Eukaryota Opisthokonta Fungi Dikarya Ascomycota saccharomyceta Pezizomycotina leotiomyceta Eurotiomycetes Eurotiomycetidae Eurotiales (green and blue molds) Aspergillaceae Aspergillus Aspergillus subgen. Nidulantes Emericella nidulans (Aspergillus nidulans) Emericella nidulans (strain FGSC A4 / ATCC 38163 / CBS 112.46 / NRRL 194 / M139) (Aspergillus nidulans) |
| Enzyme Sequence | MSSSDNYRLDGKVALVTGAGRGIGAAIAVALGQRGAKVVVNYANSREAAEKVVDEIKSNGSDAISIQADVGDPDAVTKLMDQAVEHFGYLDIVSSNAGIVSFGHVKDVTPDEFDRVFRVNTRGQFFVAREAYRHLREGGRIILTSSNTASVKGVPRHAVYSGSKGAIDTFVRCLAIDCGDKKITVNAVAPGAIKTDMFLSVSREYIPNGETFTDEQVDECAAWLSPLNRVGLPVDVARVVSFLASDAAEWISGKIIGVDGGAFR |
| Enzyme Length | 264 |
| Uniprot Accession Number | Q00791 |
| Absorption | |
| Active Site | ACT_SITE 160; /note=Proton acceptor; /evidence=ECO:0000255|PROSITE-ProRule:PRU10001 |
| Activity Regulation | |
| Binding Site | BINDING 146; /note=Substrate; /evidence=ECO:0000250; BINDING 164; /note=NADP; /evidence=ECO:0000250|UniProtKB:P16544 |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: Reaction=(4S,8R)-2,13,16,20-tetrahydroxy-7,9-dioxapentacyclo[10.8.0.0(3,10).0(4,8).0(14,19)]icosa-1(12),2,5,10,13,16,19-heptaen-18-one + H(+) + NADPH = (4S,8R,16R)-2,13,16,20-tetrahydroxy-7,9-dioxapentacyclo[10.8.0.0(3,10).0(4,8).0(14,19)]icosa-1(12),2,5,10,13,19-hexaen-18-one + NADP(+); Xref=Rhea:RHEA:64296, ChEBI:CHEBI:15378, ChEBI:CHEBI:57783, ChEBI:CHEBI:58349, ChEBI:CHEBI:150859, ChEBI:CHEBI:150860; Evidence={ECO:0000305|PubMed:8017929};PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:64297; Evidence={ECO:0000305|PubMed:8017929}; |
| DNA Binding | |
| EC Number | 1.3.1.- |
| Enzyme Function | FUNCTION: Versicolorin reductase; part of the gene cluster that mediates the biosynthesis of sterigmatocystin (ST), a polyketide-derived furanocoumarin which is part of the most toxic and carcinogenic compounds among the known mycotoxins (PubMed:8017929, PubMed:8643646). The first step in the biosynthesis of sterigmatocystin is the production of hexanoate by the fatty acid synthase (FAS) units stcJ and stcK (PubMed:8962148). The polyketide backbone is assembled by the non-reducing polyketide synthase stcA by condensation of the starter hexanoyl-CoA and 7 malonyl-CoA extender units followed by cyclization and release of norsolorinic acid (By similarity). Norsolorinic acid is the first stable intermediate in the biosynthesis of sterigmatocystin and is converted into averantin (AVN) by the ketoreductase stcE which reduces the hexanoate ketone to an alcohol (PubMed:8643646) (Probable). Averantin is then oxidized into 5'-hydroxyaverantin (HAVN) by the cytochrome P450 monooxygenase stcF (PubMed:10618248). 5'-hydroxyaverantin is further converted to 5'-oxyaverantin (OAVN) by the 5'-hydroxyaverantin dehydrogenase stcG (PubMed:24957370). The next step is the conversion of OAVN into averufin (AVF) which is catalyzed by a yet to be identified enzyme (PubMed:24957370). The cytochrome P450 monoxygenase stcB and the flavin-binding monooxygenase stcW are both required for the conversion of averufin to 1-hydroxyversicolorone (PubMed:10618248). The esterase stcI probably catalyzes the formation of versiconal hemiacetal acetate from 1-hydroxyversicolorone (PubMed:24957370). The oxydoreductase stcN then probably catalyzes the biosynthetic step from versiconal to versicolorin B (VERB) (PubMed:24957370). The next step is performed by the versicolorin B desaturase stcL to produce versicolorin A (VERA) (PubMed:8999832). The ketoreductase stcU and the cytochrome P450 monooxygenase stcS are involved in the conversion of versicolorin A to demethylsterigmatocystin (PubMed:7486998). The Baeyer-Villiger oxidas stcQ and the reductase stcR might be involved in the biosynthetic step from versicolorin A to demethylsterigmatocystin (PubMed:24957370). The final step in the biosynthesis of sterigmatocystin is the methylation of demethylsterigmatocystin catalyzed by the methyltransferase stcP (PubMed:8900026). {ECO:0000250|UniProtKB:Q12053, ECO:0000269|PubMed:10618248, ECO:0000269|PubMed:7486998, ECO:0000269|PubMed:8017929, ECO:0000269|PubMed:8643646, ECO:0000269|PubMed:8900026, ECO:0000269|PubMed:8962148, ECO:0000269|PubMed:8999832, ECO:0000303|PubMed:24957370, ECO:0000305|PubMed:8643646}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | PATHWAY: Mycotoxin biosynthesis; sterigmatocystin biosynthesis. {ECO:0000269|PubMed:8017929, ECO:0000269|PubMed:8643646}. |
| nucleotide Binding | NP_BIND 15..39; /note=NADP; /evidence=ECO:0000250; NP_BIND 16..44; /note=NADP; /evidence=ECO:0000250|UniProtKB:P16544 |
| Features | Active site (1); Binding site (2); Chain (1); Nucleotide binding (2); Sequence conflict (3) |
| Keywords | NADP;Oxidoreductase;Reference proteome |
| Interact With | |
| Induction | INDUCTION: The genes forming the sterigmatocystin biosynthesis cluster are co-regulated and induced on oatmeal porridge or the fungal isolates were grown either on oatmeal porridge or in YEC medium (0.2% yeast extract, 5.0% corn steep liquor) (PubMed:8643646, PubMed:8017929). Expression is positively regulated by the cluster-specific transcription factor aflR that binds the palindromic sequence 5'-TCG(N5)CGA-3'found in the promoter (PubMed:9680223). {ECO:0000269|PubMed:8017929, ECO:0000269|PubMed:8643646, ECO:0000269|PubMed:9680223}. |
| Subcellular Location | |
| Modified Residue | |
| Post Translational Modification | |
| Signal Peptide | |
| Structure 3D | |
| Cross Reference PDB | - |
| Mapped Pubmed ID | - |
| Motif | |
| Gene Encoded By | |
| Mass | 28,056 |
| Kinetics | |
| Metal Binding | |
| Rhea ID | RHEA:64296; RHEA:64297 |
| Cross Reference Brenda |