| IED ID | IndEnz0016000173 |
| Enzyme Type ID | tyrosinase000173 |
| Protein Name |
Cytochrome P450 monooxygenase ustC EC 1.-.-.- Ustiloxin B biosynthesis protein C |
| Gene Name | ustC AFLA_094960 |
| Organism | Aspergillus flavus (strain ATCC 200026 / FGSC A1120 / IAM 13836 / NRRL 3357 / JCM 12722 / SRRC 167) |
| Taxonomic Lineage | cellular organisms Eukaryota Opisthokonta Fungi Dikarya Ascomycota saccharomyceta Pezizomycotina leotiomyceta Eurotiomycetes Eurotiomycetidae Eurotiales (green and blue molds) Aspergillaceae Aspergillus Aspergillus subgen. Circumdati Aspergillus flavus Aspergillus flavus (strain ATCC 200026 / FGSC A1120 / IAM 13836 / NRRL 3357 / JCM 12722 / SRRC 167) |
| Enzyme Sequence | MSPFIFAVTLTFAILALGILRRRYFHPLSRFPGPFLGSVTSLYQTYWHVHPNKTLHDTELHRKYGPIVRYSPNGLIVNDPALLPVIYNRRANKTDFYAPVFDTHSTFTRKDYREHVASRKAISHAVGFLAFFRTEYSYGLVLLMIIFKQYSVTNTRLFEPQVDGILSELAGSSVTPSQLARVIFHISRNFKVQEKLYEELVAAEQDGRIPPLSAIISDEQAHRLPFLSACIREAQRYAPTMSQLPRYAPEGTGLELHEQYVPPGTSVSTSPWIIGRNKDLYGEDANSFRPERWLEASPEEERRWDHFSFHFGYGARKCLANNFGLMQLYKVAAEVCAYPIRCLLRYRAHHECRYFVVLKLKLKGRTRIQSVEGRLRVPGFALIAEQDPGHKHNGYINMDLFRA |
| Enzyme Length | 403 |
| Uniprot Accession Number | B8NM64 |
| Absorption | |
| Active Site | |
| Activity Regulation | |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | |
| DNA Binding | |
| EC Number | 1.-.-.- |
| Enzyme Function | FUNCTION: Cytochrome P450 monooxygenase; part of the gene cluster that mediates the biosynthesis of the secondary metabolite ustiloxin B, an antimitotic tetrapeptide (PubMed:24841822, PubMed:27166860, PubMed:26703898). First, ustA is processed by the subtilisin-like endoprotease Kex2 that is outside the ustiloxin B gene cluster, at the C-terminal side of Arg-Lys, after transfer to Golgi apparatus through the endoplasmic reticulum (ER) (PubMed:24841822). Cleavage by KEX2 generates 16 peptides YAIG-I to YAIG-XVI (PubMed:24841822). To process the precursor peptide further, at least two peptidases are necessary to cleave the N-terminal and C-terminal sides of the Tyr-Ala-Ile-Gly core peptide which serves as backbone for the synthesis of ustiloxin B, through cyclization and modification of the tyrosine with a non-protein coding amino acid, norvaline (PubMed:24841822). One of the two peptidases must be the serine peptidase ustP; and the other pepdidase is probably ustH (PubMed:24841822). Macrocyclization of the core peptide derived from ustA requires the tyrosinase ustQ, as well as the homologous oxidases ustYa and ustYb, and leads to the production of the first cyclization product N-desmethylustiloxin F (PubMed:27166860, PubMed:26703898). For the formation of N-desmethylustiloxin F, three oxidation steps are required, hydroxylation at the benzylic position, hydroxylation at either the aromatic ring of Tyr or beta-position of Ile, and oxidative cyclization (PubMed:27166860). UstQ may catalyze the oxidation of a phenol moiety, whereas the ustYa and ustYb are most likely responsible for the remaining two-step oxidations (PubMed:27166860). N-desmethylustiloxin F is then methylated by ustM to yield ustiloxin F which in turn substrate of the cytochrome P450 monooxygenase ustC which catalyzes the formation of S-deoxyustiloxin H (PubMed:27166860). The flavoprotein monooxygenases ustF1 and ustF2 then participate in the modification of the side chain of S-deoxyustiloxin H, leading to the synthesis of an oxime intermediate, via ustiloxin H (PubMed:27166860). Finally, carboxylative dehydration performed by the cysteine desulfurase-like protein ustD yields ustiloxin B (PubMed:27166860). {ECO:0000269|PubMed:24841822, ECO:0000269|PubMed:26703898, ECO:0000269|PubMed:27166860}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | PATHWAY: Mycotoxin biosynthesis. {ECO:0000269|PubMed:24841822}. |
| nucleotide Binding | |
| Features | Chain (1); Glycosylation (2); Metal binding (1); Signal peptide (1) |
| Keywords | Glycoprotein;Heme;Iron;Metal-binding;Monooxygenase;Oxidoreductase;Reference proteome;Signal |
| Interact With | |
| Induction | |
| Subcellular Location | |
| Modified Residue | |
| Post Translational Modification | |
| Signal Peptide | SIGNAL 1..18; /evidence=ECO:0000255 |
| Structure 3D | |
| Cross Reference PDB | - |
| Mapped Pubmed ID | - |
| Motif | |
| Gene Encoded By | |
| Mass | 46,402 |
| Kinetics | |
| Metal Binding | METAL 318; /note=Iron (heme axial ligand); /evidence=ECO:0000250|UniProtKB:P04798 |
| Rhea ID | |
| Cross Reference Brenda |