CITB_MONRU
ID CITB_MONRU Reviewed; 329 AA.
AC A0A159BP93;
DT 07-JUN-2017, integrated into UniProtKB/Swiss-Prot.
DT 06-JUL-2016, sequence version 1.
DT 03-AUG-2022, entry version 16.
DE RecName: Full=2-oxoglutarate-dependent dioxygenase citB {ECO:0000303|Ref.1};
DE EC=1.14.-.- {ECO:0000269|Ref.1};
DE AltName: Full=Citrinin synthesis protein B {ECO:0000303|Ref.1};
GN Name=citB {ECO:0000303|Ref.1}; Synonyms=mrl2 {ECO:0000303|Ref.1};
OS Monascus ruber (Mold).
OC Eukaryota; Fungi; Dikarya; Ascomycota; Pezizomycotina; Eurotiomycetes;
OC Eurotiomycetidae; Eurotiales; Aspergillaceae; Monascus.
OX NCBI_TaxID=89489;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, DISRUPTION PHENOTYPE,
RP CATALYTIC ACTIVITY, AND PATHWAY.
RC STRAIN=M7;
RX DOI=10.1039/C5SC04027B;
RA He Y., Cox R.J.;
RT "The molecular steps of citrinin biosynthesis in fungi.";
RL Chem. Sci. 7:2119-2127(2016).
RN [2]
RP INDUCTION.
RC STRAIN=M7;
RX PubMed=27998068; DOI=10.1021/acs.jafc.6b04056;
RA Wang L., Dai Y., Chen W., Shao Y., Chen F.;
RT "Effects of light intensity and color on the biomass, extracellular red
RT pigment, and citrinin production of Monascus ruber.";
RL J. Agric. Food Chem. 64:9506-9514(2016).
RN [3]
RP FUNCTION.
RX PubMed=29189834; DOI=10.1039/c7cc07079a;
RA Storm P.A., Townsend C.A.;
RT "In trans hydrolysis of carrier protein-bound acyl intermediates by CitA
RT during citrinin biosynthesis.";
RL Chem. Commun. (Camb.) 54:50-53(2017).
CC -!- FUNCTION: Non-reducing polyketide synthase; part of the gene cluster
CC that mediates the biosynthesis of the mycotoxin citrinin, a hepato-
CC nephrotoxic compound to humans due to inhibition of respiration complex
CC III (Ref.1). The pathway begins with the synthesis of a keto-aldehyde
CC intermediate by the citrinin PKS (pksCT also named citS) from
CC successive condensations of 4 malonyl-CoA units, presumably with a
CC simple acetyl-CoA starter unit (Ref.1). Release of the keto-aldehyde
CC intermediate is consistent with the presence of the C-terminal
CC reductive release domain (Ref.1). CitA collaborates with citS by
CC catalyzing the hydrolysis of ACP-bound acyl intermediates to free the
CC ACP from stalled intermediates (PubMed:29189834). CitB then catalyzes
CC the oxidation of the C-12 methyl of the ketone intermediate to an
CC alcohol intermediate which is further oxidized by the oxidoreductase
CC citC to produce a bisaldehyde intermediate (Ref.1). The fourth
CC catalytic step is catalyzed by the citD aldehyde dehydrogenase (Ref.1).
CC The final transformation is the reduction of C-3 by citE to provide the
CC chemically stable citrinin nucleus (Ref.1). CitE appears highly
CC selective for its substrate as its presence in any context other than a
CC full complement of citS and citA-D does not result in observable new
CC compounds (Ref.1). {ECO:0000269|PubMed:29189834, ECO:0000269|Ref.1}.
CC -!- COFACTOR:
CC Name=Fe(2+); Xref=ChEBI:CHEBI:29033;
CC Evidence={ECO:0000255|PROSITE-ProRule:PRU00805};
CC Note=Binds 1 Fe(2+) ion per subunit. {ECO:0000255|PROSITE-
CC ProRule:PRU00805};
CC -!- PATHWAY: Mycotoxin biosynthesis. {ECO:0000269|Ref.1}.
CC -!- INDUCTION: Expression is stimulated under green light conditions
CC (PubMed:27998068). {ECO:0000269|PubMed:27998068}.
CC -!- DISRUPTION PHENOTYPE: Leads to complete absence of citrinin production
CC and the accumulation of a keto-aldehyde intermediate at the same
CC retention time which is distinguishable by its UV and mass spectra
CC (Ref.1). {ECO:0000269|Ref.1}.
CC -!- SIMILARITY: Belongs to the iron/ascorbate-dependent oxidoreductase
CC family. {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; KT781075; ALI92653.1; -; Genomic_DNA.
DR AlphaFoldDB; A0A159BP93; -.
DR SMR; A0A159BP93; -.
DR GO; GO:0051213; F:dioxygenase activity; IEA:UniProtKB-KW.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR Gene3D; 2.60.120.330; -; 1.
DR InterPro; IPR026992; DIOX_N.
DR InterPro; IPR044861; IPNS-like_FE2OG_OXY.
DR InterPro; IPR027443; IPNS-like_sf.
DR InterPro; IPR005123; Oxoglu/Fe-dep_dioxygenase.
DR Pfam; PF03171; 2OG-FeII_Oxy; 1.
DR Pfam; PF14226; DIOX_N; 1.
DR PROSITE; PS51471; FE2OG_OXY; 1.
PE 1: Evidence at protein level;
KW Dioxygenase; Iron; Metal-binding; Oxidoreductase.
FT CHAIN 1..329
FT /note="2-oxoglutarate-dependent dioxygenase citB"
FT /id="PRO_0000440317"
FT DOMAIN 183..288
FT /note="Fe2OG dioxygenase"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00805"
FT BINDING 211
FT /ligand="Fe cation"
FT /ligand_id="ChEBI:CHEBI:24875"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00805"
FT BINDING 213
FT /ligand="Fe cation"
FT /ligand_id="ChEBI:CHEBI:24875"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00805"
FT BINDING 269
FT /ligand="Fe cation"
FT /ligand_id="ChEBI:CHEBI:24875"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00805"
FT BINDING 279
FT /ligand="2-oxoglutarate"
FT /ligand_id="ChEBI:CHEBI:16810"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00805"
SQ SEQUENCE 329 AA; 36894 MW; 08E466646DCF4C59 CRC64;
MPISTKSSFY LPAVDISPYL QDPNSDAARK VIDDVRAACT STGFFQLLGH GISPALQQSV
FAAAAKFFAL PSDVKSRCRN VGFRGYDPMA SQSYELGVLP DLKEGFIAGK DIPLDDPRVA
SQRFFMGQNA WPPSELLPEA NFRRPIEEYY QAMLKLCWVV LDLVAATLPY GPHVFDEFKE
NDPACPLRLL HYPPAPAPDV AKGRQLGSSA HTDFGAITLL LQDDHSGLEV QDCETGEWIG
VPPNKDAYVV NLGDMMSRIT RGHYKSSIHR VINQNLTDRY SVVFFFDGNL DYRLRPLDRV
GQNWDEEDTL TVEEHMLERT TTTYNLKVK
