AFLO_ASPPU
ID AFLO_ASPPU Reviewed; 386 AA.
AC Q9UQY0; A0A0F0HZ60; Q6UEF8;
DT 01-MAY-2013, integrated into UniProtKB/Swiss-Prot.
DT 05-JUL-2004, sequence version 2.
DT 03-AUG-2022, entry version 79.
DE RecName: Full=Demethylsterigmatocystin 6-O-methyltransferase {ECO:0000305|PubMed:10543813};
DE EC=2.1.1.109 {ECO:0000269|PubMed:10543813, ECO:0000269|PubMed:16349476};
DE AltName: Full=Aflatoxin biosynthesis protein O {ECO:0000303|PubMed:15006741};
DE AltName: Full=O-methyltransferase I {ECO:0000303|PubMed:10543813};
DE Short=mt-I {ECO:0000303|PubMed:10543813};
GN Name=aflO {ECO:0000303|PubMed:15006741};
GN Synonyms=dmtA {ECO:0000303|PubMed:10543813},
GN omtB {ECO:0000303|PubMed:10806361}; ORFNames=P875_00052999-2;
OS Aspergillus parasiticus (strain ATCC 56775 / NRRL 5862 / SRRC 143 / SU-1).
OC Eukaryota; Fungi; Dikarya; Ascomycota; Pezizomycotina; Eurotiomycetes;
OC Eurotiomycetidae; Eurotiales; Aspergillaceae; Aspergillus.
OX NCBI_TaxID=1403190;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA], PROTEIN SEQUENCE OF 2-47,
RP FUNCTION, PATHWAY, AND CATALYTIC ACTIVITY.
RC STRAIN=NIAH-26;
RX PubMed=10543813; DOI=10.1128/aem.65.11.4987-4994.1999;
RA Motomura M., Chihaya N., Shinozawa T., Hamasaki T., Yabe K.;
RT "Cloning and characterization of the O-methyltransferase I gene (dmtA) from
RT Aspergillus parasiticus associated with the conversions of
RT demethylsterigmatocystin to sterigmatocystin and
RT dihydrodemethylsterigmatocystin to dihydrosterigmatocystin in aflatoxin
RT biosynthesis.";
RL Appl. Environ. Microbiol. 65:4987-4994(1999).
RN [2]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], AND FUNCTION.
RC STRAIN=ATCC 56775 / NRRL 5862 / SRRC 143 / SU-1;
RX PubMed=10806361; DOI=10.1016/s0378-1119(00)00126-8;
RA Yu J., Woloshuk C.P., Bhatnagar D., Cleveland T.E.;
RT "Cloning and characterization of avfA and omtB genes involved in aflatoxin
RT biosynthesis in three Aspergillus species.";
RL Gene 248:157-167(2000).
RN [3]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=ATCC 56775 / NRRL 5862 / SRRC 143 / SU-1;
RA Yu J., Fedorova N., Yin Y., Losada L., Zafar N., Taujale R., Ehrlich K.C.,
RA Bhatnagar D., Cleveland T.E., Bennett J.W., Nierman W.C.;
RT "Draft genome sequence of Aspergillus parasiticus SU-1.";
RL Submitted (FEB-2015) to the EMBL/GenBank/DDBJ databases.
RN [4]
RP FUNCTION.
RX PubMed=1339261; DOI=10.1128/aem.58.11.3527-3537.1992;
RA Skory C.D., Chang P.K., Cary J., Linz J.E.;
RT "Isolation and characterization of a gene from Aspergillus parasiticus
RT associated with the conversion of versicolorin A to sterigmatocystin in
RT aflatoxin biosynthesis.";
RL Appl. Environ. Microbiol. 58:3527-3537(1992).
RN [5]
RP FUNCTION.
RX PubMed=8434913; DOI=10.1128/aem.59.2.479-484.1993;
RA Keller N.P., Dischinger H.C. Jr., Bhatnager D., Cleveland T.E.,
RA Ullah A.H.J.;
RT "Purification of a 40-kilodalton methyltransferase active in the aflatoxin
RT biosynthetic pathway.";
RL Appl. Environ. Microbiol. 59:479-484(1993).
RN [6]
RP FUNCTION.
RX PubMed=8368836; DOI=10.1128/aem.59.8.2486-2492.1993;
RA Yabe K., Matsuyama Y., Ando Y., Nakajima H., Hamasaki T.;
RT "Stereochemistry during aflatoxin biosynthesis: conversion of norsolorinic
RT acid to averufin.";
RL Appl. Environ. Microbiol. 59:2486-2492(1993).
RN [7]
RP FUNCTION.
RX PubMed=8368837; DOI=10.1128/aem.59.8.2493-2500.1993;
RA Yabe K., Hamasaki T.;
RT "Stereochemistry during aflatoxin biosynthesis: cyclase reaction in the
RT conversion of versiconal to versicolorin B and racemization of versiconal
RT hemiacetal acetate.";
RL Appl. Environ. Microbiol. 59:2493-2500(1993).
RN [8]
RP FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, AND CATALYTIC ACTIVITY.
RX PubMed=16349476; DOI=10.1128/aem.64.1.166-171.1998;
RA Yabe K., Matsushima K., Koyama T., Hamasaki T.;
RT "Purification and characterization of O-methyltransferase I involved in
RT conversion of demethylsterigmatocystin to sterigmatocystin and of
RT dihydrodemethylsterigmatocystin to dihydrosterigmatocystin during aflatoxin
RT biosynthesis.";
RL Appl. Environ. Microbiol. 64:166-171(1998).
RN [9]
RP FUNCTION.
RX PubMed=10584035; DOI=10.1128/aem.65.12.5639-5641.1999;
RA Zhou R., Linz J.E.;
RT "Enzymatic function of the nor-1 protein in aflatoxin biosynthesis in
RT Aspergillus parasiticus.";
RL Appl. Environ. Microbiol. 65:5639-5641(1999).
RN [10]
RP FUNCTION.
RX PubMed=11055914; DOI=10.1128/aem.66.11.4715-4719.2000;
RA Chang P.K., Yu J., Ehrlich K.C., Boue S.M., Montalbano B.G., Bhatnagar D.,
RA Cleveland T.E.;
RT "adhA in Aspergillus parasiticus is involved in conversion of 5'-
RT hydroxyaverantin to averufin.";
RL Appl. Environ. Microbiol. 66:4715-4719(2000).
RN [11]
RP FUNCTION.
RX PubMed=16256699; DOI=10.1006/bioo.2001.1216;
RA Hitchman T.S., Schmidt E.W., Trail F., Rarick M.D., Linz J.E.,
RA Townsend C.A.;
RT "Hexanoate synthase, a specialized type I fatty acid synthase in aflatoxin
RT B1 biosynthesis.";
RL Bioorg. Chem. 29:293-307(2001).
RN [12]
RP FUNCTION.
RX PubMed=11996570; DOI=10.1021/ja012185v;
RA Udwary D.W., Casillas L.K., Townsend C.A.;
RT "Synthesis of 11-hydroxyl O-methylsterigmatocystin and the role of a
RT cytochrome P-450 in the final step of aflatoxin biosynthesis.";
RL J. Am. Chem. Soc. 124:5294-5303(2002).
RN [13]
RP REVIEW, FUNCTION, PATHWAY, AND NOMENCLATURE.
RX PubMed=15006741; DOI=10.1128/aem.70.3.1253-1262.2004;
RA Yu J., Chang P.K., Ehrlich K.C., Cary J.W., Bhatnagar D., Cleveland T.E.,
RA Payne G.A., Linz J.E., Woloshuk C.P., Bennett J.W.;
RT "Clustered pathway genes in aflatoxin biosynthesis.";
RL Appl. Environ. Microbiol. 70:1253-1262(2004).
RN [14]
RP FUNCTION.
RX PubMed=15528514; DOI=10.1128/aem.70.11.6518-6524.2004;
RA Ehrlich K.C., Chang P.K., Yu J., Cotty P.J.;
RT "Aflatoxin biosynthesis cluster gene cypA is required for G aflatoxin
RT formation.";
RL Appl. Environ. Microbiol. 70:6518-6524(2004).
RN [15]
RP FUNCTION.
RX PubMed=15932995; DOI=10.1128/aem.71.6.2999-3006.2005;
RA Sakuno E., Wen Y., Hatabayashi H., Arai H., Aoki C., Yabe K., Nakajima H.;
RT "Aspergillus parasiticus cyclase catalyzes two dehydration steps in
RT aflatoxin biosynthesis.";
RL Appl. Environ. Microbiol. 71:2999-3006(2005).
RN [16]
RP FUNCTION.
RX PubMed=16332900; DOI=10.1128/aem.71.12.8963-8965.2005;
RA Ehrlich K.C., Montalbano B., Boue S.M., Bhatnagar D.;
RT "An aflatoxin biosynthesis cluster gene encodes a novel oxidase required
RT for conversion of versicolorin a to sterigmatocystin.";
RL Appl. Environ. Microbiol. 71:8963-8965(2005).
RN [17]
RP FUNCTION.
RX PubMed=15771506; DOI=10.1021/ja0455188;
RA Henry K.M., Townsend C.A.;
RT "Ordering the reductive and cytochrome P450 oxidative steps in
RT demethylsterigmatocystin formation yields general insights into the
RT biosynthesis of aflatoxin and related fungal metabolites.";
RL J. Am. Chem. Soc. 127:3724-3733(2005).
RN [18]
RP FUNCTION.
RX PubMed=16461654; DOI=10.1128/aem.72.2.1096-1101.2006;
RA Cary J.W., Ehrlich K.C., Bland J.M., Montalbano B.G.;
RT "The aflatoxin biosynthesis cluster gene, aflX, encodes an oxidoreductase
RT involved in conversion of versicolorin A to demethylsterigmatocystin.";
RL Appl. Environ. Microbiol. 72:1096-1101(2006).
RN [19]
RP FUNCTION.
RX PubMed=18486503; DOI=10.1016/j.fgb.2008.03.003;
RA Cai J., Zeng H., Shima Y., Hatabayashi H., Nakagawa H., Ito Y., Adachi Y.,
RA Nakajima H., Yabe K.;
RT "Involvement of the nadA gene in formation of G-group aflatoxins in
RT Aspergillus parasiticus.";
RL Fungal Genet. Biol. 45:1081-1093(2008).
RN [20]
RP FUNCTION.
RX PubMed=18403714; DOI=10.1126/science.1154711;
RA Crawford J.M., Thomas P.M., Scheerer J.R., Vagstad A.L., Kelleher N.L.,
RA Townsend C.A.;
RT "Deconstruction of iterative multidomain polyketide synthase function.";
RL Science 320:243-246(2008).
CC -!- FUNCTION: Demethylsterigmatocystin 6-O-methyltransferase; part of the
CC gene cluster that mediates the biosynthesis of aflatoxins, a group of
CC polyketide-derived furanocoumarins, and part of the most toxic and
CC carcinogenic compounds among the known mycotoxins (PubMed:15006741).
CC The four major aflatoxins produced by A.parasiticus are aflatoxin B1
CC (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2
CC (AFG2) (PubMed:15006741). The first step of the pathway is the
CC conversion of acetate to norsolorinic acid (NOR) and requires the fatty
CC acid synthase subunits aflA and aflB, as well as the PKS aflC
CC (PubMed:15006741). AflC combines a hexanoyl starter unit and 7 malonyl-
CC CoA extender units to synthesize the precursor NOR (PubMed:18403714).
CC The hexanoyl starter unit is provided to the acyl-carrier protein (ACP)
CC domain by the fungal fatty acid synthase aflA/aflB (PubMed:16256699).
CC The second step is the conversion of NOR to averantin (AVN) and
CC requires the norsolorinic acid ketoreductase aflD, which catalyzes the
CC dehydration of norsolorinic acid to form (1'S)-averantin
CC (PubMed:10584035). The norsolorinic acid reductases aflE and aflF may
CC also play a role in the conversion of NOR to AVN (PubMed:15006741). The
CC cytochrome P450 monooxygenase aflG then catalyzes the hydroxylation of
CC AVN to 5'hydroxyaverantin (HAVN) (PubMed:8368836). The next step is
CC performed by the 5'-hydroxyaverantin dehydrogenase aflH that transforms
CC HAVN to 5'-oxoaverantin (OAVN) which is further converted to averufin
CC (AVF) by aflK that plays a dual role in the pathway, as a 5'-
CC oxoaverantin cyclase that mediates conversion of 5'-oxoaverantin, as
CC well as a versicolorin B synthase in a later step in the pathway
CC (PubMed:15006741, PubMed:11055914, PubMed:15932995). The averufin
CC oxidase aflI catalyzes the conversion of AVF to versiconal hemiacetal
CC acetate (VHA) (PubMed:15006741). VHA is then the substrate for the
CC versiconal hemiacetal acetate esterase aflJ to yield versiconal (VAL)
CC (PubMed:15006741). Versicolorin B synthase aflK then converts VAL to
CC versicolorin B (VERB) by closing the bisfuran ring of aflatoxin which
CC is required for DNA-binding, thus giving to aflatoxin its activity as a
CC mutagen (PubMed:15006741, PubMed:8368837, PubMed:15932995). Then, the
CC activity of the versicolorin B desaturase aflL leads to versicolorin A
CC (VERA) (PubMed:15006741, PubMed:8368837). A branch point starts from
CC VERB since it can also be converted to dihydrodemethylsterigmatocystin
CC (DMDHST), probably also by aflL, VERA being a precursor for aflatoxins
CC B1 and G1, and DMDHST for aflatoxins B2 and G2 (PubMed:15006741). Next,
CC the versicolorin reductase aflM and the cytochrome P450 monooxygenase
CC aflN are involved in conversion of VERA to demethylsterigmatocystin
CC (DMST) (PubMed:15006741, PubMed:1339261, PubMed:15771506). AflX and
CC aflY seem also involved in this step, through probable aflX-mediated
CC epoxide ring-opening step following versicolorin A oxidation and aflY-
CC mediated Baeyer-Villiger oxidation required for the formation of the
CC xanthone ring (PubMed:16332900, PubMed:16461654). The methyltransferase
CC aflO then leads to the modification of DMST to sterigmatocystin (ST),
CC and of DMDHST to dihydrosterigmatocystin (DHST) (PubMed:10543813,
CC PubMed:10806361, PubMed:16349476). Both ST and DHST are then substrates
CC of the O-methyltransferase aflP to yield O-methylsterigmatocystin
CC (OMST) and dihydro-O-methylsterigmatocystin (DHOMST), respectively
CC (PubMed:8434913). Finally OMST is converted to aflatoxins B1 and G1,
CC and DHOMST to aflatoxins B2 and G2, via the action of several enzymes
CC including O-methylsterigmatocystin oxidoreductase aflQ, the cytochrome
CC P450 monooxygenase aflU, but also the NADH-dependent flavin
CC oxidoreductase nadA which is specifically required for the synthesis of
CC AFG1 (PubMed:15006741, PubMed:11996570, PubMed:15528514,
CC PubMed:18486503). {ECO:0000269|PubMed:10543813,
CC ECO:0000269|PubMed:10584035, ECO:0000269|PubMed:10806361,
CC ECO:0000269|PubMed:11055914, ECO:0000269|PubMed:11996570,
CC ECO:0000269|PubMed:1339261, ECO:0000269|PubMed:15528514,
CC ECO:0000269|PubMed:15771506, ECO:0000269|PubMed:15932995,
CC ECO:0000269|PubMed:16256699, ECO:0000269|PubMed:16332900,
CC ECO:0000269|PubMed:16349476, ECO:0000269|PubMed:16461654,
CC ECO:0000269|PubMed:18403714, ECO:0000269|PubMed:18486503,
CC ECO:0000269|PubMed:8368836, ECO:0000269|PubMed:8368837,
CC ECO:0000269|PubMed:8434913, ECO:0000305|PubMed:15006741}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=6-demethylsterigmatocystin + S-adenosyl-L-methionine = H(+) +
CC S-adenosyl-L-homocysteine + sterigmatocystin; Xref=Rhea:RHEA:11504,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:18227, ChEBI:CHEBI:18236,
CC ChEBI:CHEBI:57856, ChEBI:CHEBI:59789; EC=2.1.1.109;
CC Evidence={ECO:0000269|PubMed:10543813};
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=0.94 M for demethylsterigmatocystin {ECO:0000269|PubMed:16349476};
CC KM=2.5 uM for dihydrodemethylsterigmatocystin
CC {ECO:0000269|PubMed:16349476};
CC pH dependence:
CC Optimum pH is 6.5-9.0. {ECO:0000269|PubMed:16349476};
CC -!- PATHWAY: Mycotoxin biosynthesis; aflatoxin biosynthesis.
CC {ECO:0000269|PubMed:10543813, ECO:0000305|PubMed:15006741}.
CC -!- SIMILARITY: Belongs to the class I-like SAM-binding methyltransferase
CC superfamily. Cation-independent O-methyltransferase family. COMT
CC subfamily. {ECO:0000255|PROSITE-ProRule:PRU01020}.
CC -!- SEQUENCE CAUTION:
CC Sequence=KJK60770.1; Type=Erroneous gene model prediction; Note=The predicted gene P875_00052999 has been split into 2 genes: P875_00052999-1 (aflP) and P875_00052999-2 (aflO).; Evidence={ECO:0000305};
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; AB022905; BAA86103.1; -; Genomic_DNA.
DR EMBL; AB022906; BAA86104.1; -; mRNA.
DR EMBL; AY371490; AAS66016.1; -; Genomic_DNA.
DR EMBL; JZEE01000729; KJK60770.1; ALT_SEQ; Genomic_DNA.
DR AlphaFoldDB; Q9UQY0; -.
DR SMR; Q9UQY0; -.
DR BioCyc; MetaCyc:MON-14042; -.
DR BRENDA; 2.1.1.109; 523.
DR UniPathway; UPA00287; -.
DR Proteomes; UP000033540; Unassembled WGS sequence.
DR GO; GO:0047145; F:demethylsterigmatocystin 6-O-methyltransferase activity; IDA:UniProtKB.
DR GO; GO:0045122; P:aflatoxin biosynthetic process; IDA:UniProtKB.
DR GO; GO:0032259; P:methylation; IEA:UniProtKB-KW.
DR Gene3D; 1.10.10.10; -; 1.
DR Gene3D; 3.40.50.150; -; 1.
DR InterPro; IPR016461; COMT-like.
DR InterPro; IPR001077; O_MeTrfase_dom.
DR InterPro; IPR029063; SAM-dependent_MTases_sf.
DR InterPro; IPR036388; WH-like_DNA-bd_sf.
DR InterPro; IPR036390; WH_DNA-bd_sf.
DR Pfam; PF00891; Methyltransf_2; 1.
DR PIRSF; PIRSF005739; O-mtase; 1.
DR SUPFAM; SSF46785; SSF46785; 1.
DR SUPFAM; SSF53335; SSF53335; 1.
DR PROSITE; PS51683; SAM_OMT_II; 1.
PE 1: Evidence at protein level;
KW Direct protein sequencing; Methyltransferase; Reference proteome;
KW S-adenosyl-L-methionine; Transferase.
FT INIT_MET 1
FT /note="Removed"
FT /evidence="ECO:0000269|PubMed:10543813"
FT CHAIN 2..386
FT /note="Demethylsterigmatocystin 6-O-methyltransferase"
FT /id="PRO_5000049327"
FT REGION 177..197
FT /note="Substrate binding"
FT /evidence="ECO:0000250"
FT ACT_SITE 293
FT /note="Proton acceptor"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01020"
FT BINDING 137..150
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 228..229
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:O04385"
FT BINDING 253
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:O04385"
FT BINDING 273..274
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:O04385"
FT BINDING 289
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:O04385"
FT CONFLICT 8
FT /note="I -> T (in Ref. 2; AAS66016 and 3; KJK60770)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 386 AA; 43155 MW; 1C25C2EE5F3F6114 CRC64;
MTGLDMEIIF AKIKEEYART DDVGKRQIQG HIRELQVGFY SDWDVVMRLS SGPLQVALTK
VGIDLGIFRS LKESDTPITL AEIVKKTGAS PRLLGRILRT QAAFGLIKET GPQEYTSSAF
TDVFANSDAA GAVVQLFDIS GPCTQILPDF LAERNYQDIT SNKDCVFQKA FGSDLTMFEW
MPQHPKHMES LGHLMALERP VSWVDHYPVL EELGGFPAPD KVLMVDIGGG FGQQSKALRA
KFPDLPGRLI VQDIPQTLAN AQPAAGIEFM EHNFFEPQPI QNAKFYYLRH VFHDWPDEQC
VLILKQIIPA MGPESQILID EMVIPSTGVP WQAAFTDLLM MNSLGGVERT RAEWDDLMEQ
VGLEIIQSKV YDSKEQAILV AVPKRT
