Protein: Kotanin synthase (A2QK66)
Organism: Aspergillus niger (strain ATCC MYA-4892 / CBS 513.88 / FGSC A1513)
Function: Non-reducing polyketide synthase; part of the gene cluster that mediates the biosynthesis of the bicoumarin kotanin. The non-reducing polyketide synthase ktnS first catalyzes the formation of the pentaketidic 4,7- dihydroxy-5-methylcoumarin from acetyl coenzyme A and 4 malonyl coenzyme A molecules. Further O- methylation by ktnB leads to the formation of 7-demethylsiderin. Then, an oxidative phenol coupling catalyzed by the cytochrome P450 monooxygenase ktnC forms the 8,8'-dimer P-orlandin via dimerization the monomeric precursor, 7-demethylsiderin. P-orlandin is subsequently O-methylated in a stepwise fashion to demethylkotanin and kotanin
Sequence: MLADMCVGVYKAAMNYEIRPHEFSFNTQESLFTGLGLGFLAATAVVASPSLLDLPITAAEVVRIAMRAGILLYQKSQDLEQLSLDSSLESWTTVVRGLDESIVRGELEKFNKSMETPPSSRIYISVVEPDGSVFISGPPSGLREFFNKSGKVQSAPRAPLPVYGGPCHAAHLYDRTHTEWVVSKVNPEIASRRLSGHPLVLSMGDGQPLAGENARDLFESATYVLLTSIIRWDSVLAAVKKLPHWKQDTKLQLETFRPSSPAVHGLISAVQSEYPDCTVSVDDLGDWIIDNSLEPPTIPIDSRIAVVGMSCRLPGGSDDLQRFWELLEDGRDVHQKVPGNRYDVESHTDMTGRRLNTSHTPFGCFIDSPGLFDASFFDMSPREAGQTDPTHRLALLTAYEALEYSGYVPNRTRSTTRDRVGTVYGQCSDDYREANAGQNIDMYFIPGNYRAFAPGRISYFFKFSGPSFNCDTACSASLAAVQIACSALIRGEADMVVAGGLNILTGSDSFAGLSRGFFLSKTGNCKVFDDGADGYCRADGIGSIVLKRLSDAQQDNDNILGVILGTATNHSSHAISITHPHAPTQEHLYRSVLSQAGIGPHDVDLVEMHGTGTQAGDAAEIESVTRVFSPPVPRRSHPLYISSVKANLGHGEAAAGITALMKALLIFQHNAIPRHVGIKTALNSKFPDLERLNVHIPKETIPWPYRSNRKRYVMINNFSAAGGNTSLLLEEPPVRPDPQGPPQTRFVVALSAKSTTSLRRNLESLITWLEGNRSARLASLAYTTTARRMHHKHRIAVHGASVAEIIQALHQRGSRAELGLLVSKPPSVAFIFSGQGSFYAGVGSQLFKEYPPYREQLQRLDEICQQNGFGSILPAITDTDADVSQLSALVTQLTTVCVQIALCRLWRTLGVKPAVVIGASLGEYAALYAAGALSASDAIFLVGQRTLLMQKLCTANSYGMLAVQGSVDDIRRCVQDRTYEVACINAPRSITICASIKDIVDIQQSLVSQGYRSVKLNVPFAFHSSQMDPILDRYEEIAKAVSFRSLQIPLISSTLADAAVQSRSLVASLFLRENTRAPARFAEAVAKAQDMGLVNSHTVWVEIGVHSTYSGAVRATVADLQAIVPSLRSDETNWHTLAVSMCTLQETGVPLDWNEWYRPFEPEVRLLDLPSYRWDLKNHWIQYNGDWLLVKDKRPRTDQISAATPSLRTALVHQIMEESFRPDGGEIVVQSDVMDKEFFAVASGHKMSGRPLVSVFSYPDIAFTLARYMYSRLKPESPLPAMDFGQVRVLQGLLPRKDRSKPQWVRMRMRADPQCAALQLSISGLSDESSRHVEEKLASGVVRCGDRQSWQDEWADYAHLLTTRIVTLQQMAENGQASRVSRDLVYTLFKNIVDYADHYRGIQSAVLHGLEAVADVILAPSNDSRWTAPPHHIDPITHVGGLVLNAGHATDHHNTIYVMEGWKSMRFAEELVAGELYRSYVKMNPARDGSGFFVGDVYVMREDHIVGKVRGMTLRPLPRILMNRFFDPPDDGDGLATQHIQPHDLPQVQHQPSPTTDSGPDDDPKDPNTGPLTPEVDLPVAPSVEKANTKLVRGALALLAAETGVEPDGLTDETEVSALGIDSLLSLVLVEKFATELQVNIQSSFFLESPTIRELKEYLTASW
InterPro domains: - IPR001227: Acyl transferase domain superfamily (homologous_superfamily) [829-1134]
- IPR049900: Polyketide synthase, dehydratase domain (domain) [1213-1523]
- IPR016036: Malonyl-CoA ACP transacylase, ACP-binding (homologous_superfamily) [957-1018]
- IPR020841: Polyketide synthase, beta-ketoacyl synthase domain (domain) [301-734]
- IPR016039: Thiolase-like (homologous_superfamily) [300-737]
- IPR050091: Polyketide and Nonribosomal Peptide Biosynthesis Enzymes (family) [303-1499]
- IPR042104: Polyketide synthase, dehydratase domain superfamily (homologous_superfamily) [1207-1527]
- IPR009081: Phosphopantetheine binding ACP domain (domain) [1586-1663]
- IPR030918: Polyketide product template domain (domain) [1209-1527]
- IPR020806: Polyketide synthase-like, phosphopantetheine-binding domain (domain) [1592-1663]
- IPR014043: Acyl transferase domain (domain) [830-1149]
- IPR036736: ACP-like superfamily (homologous_superfamily) [1592-1661]
- IPR032088: Starter unit:ACP transacylase, SAT domain (domain) [20-164]
- IPR014030: Beta-ketoacyl synthase-like, N-terminal (domain) [302-552]
- IPR016035: Acyl transferase/acyl hydrolase/lysophospholipase (homologous_superfamily) [828-1126]
- IPR014031: Beta-ketoacyl synthase, C-terminal (domain) [560-677]
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0003824 (catalytic activity), GO:0016491 (oxidoreductase activity), GO:0016679 (oxidoreductase activity, acting on diphenols and related substances as donors), GO:0016682 (oxidoreductase activity, acting on diphenols and related substances as donors, oxygen as acceptor)
Biological Process (BP): GO:0008150 (biological process), GO:0008152 (metabolic process), GO:0009987 (cellular process), GO:0009058 (biosynthetic process), GO:0044237 (cellular metabolic process), GO:0019748 (secondary metabolic process), GO:0071704 (organic substance metabolic process), GO:0044550 (secondary metabolite biosynthetic process), GO:0044249 (cellular biosynthetic process), GO:0006725 (cellular aromatic compound metabolic process), GO:1901360 (organic cyclic compound metabolic process), GO:1901576 (organic substance biosynthetic process), GO:0046483 (heterocycle metabolic process), GO:1901362 (organic cyclic compound biosynthetic process), GO:0019438 (aromatic compound biosynthetic process), GO:0018130 (heterocycle biosynthetic process)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0005737 (cytoplasm), GO:0043229 (intracellular organelle), GO:0005739 (mitochondrion), GO:0043227 (membrane-bounded organelle), GO:0043231 (intracellular membrane-bounded organelle)