ID A0A1W1X6T2_9BACT Unreviewed; 153 AA.
AC A0A1W1X6T2;
DT 07-JUN-2017, integrated into UniProtKB/TrEMBL.
DT 07-JUN-2017, sequence version 1.
DT 18-JUN-2025, entry version 32.
DE RecName: Full=6,7-dimethyl-8-ribityllumazine synthase {ECO:0000256|ARBA:ARBA00072606, ECO:0000256|HAMAP-Rule:MF_00178};
DE Short=DMRL synthase {ECO:0000256|HAMAP-Rule:MF_00178};
DE Short=LS {ECO:0000256|HAMAP-Rule:MF_00178};
DE Short=Lumazine synthase {ECO:0000256|HAMAP-Rule:MF_00178};
DE EC=2.5.1.78 {ECO:0000256|ARBA:ARBA00012664, ECO:0000256|HAMAP-Rule:MF_00178};
GN Name=ribH {ECO:0000256|HAMAP-Rule:MF_00178};
GN ORFNames=SAMN02746041_00740 {ECO:0000313|EMBL:SMC19645.1};
OS Desulfacinum hydrothermale DSM 13146.
OC Bacteria; Pseudomonadati; Thermodesulfobacteriota; Syntrophobacteria;
OC Syntrophobacterales; Syntrophobacteraceae; Desulfacinum.
OX NCBI_TaxID=1121390 {ECO:0000313|EMBL:SMC19645.1, ECO:0000313|Proteomes:UP000192783};
RN [1] {ECO:0000313|EMBL:SMC19645.1, ECO:0000313|Proteomes:UP000192783}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=DSM 13146 {ECO:0000313|EMBL:SMC19645.1,
RC ECO:0000313|Proteomes:UP000192783};
RA Afonso C.L., Miller P.J., Scott M.A., Spackman E., Goraichik I.,
RA Dimitrov K.M., Suarez D.L., Swayne D.E.;
RL Submitted (APR-2017) to the EMBL/GenBank/DDBJ databases.
CC -!- FUNCTION: Catalyzes the formation of 6,7-dimethyl-8-ribityllumazine by
CC condensation of 5-amino-6-(D-ribitylamino)uracil with 3,4-dihydroxy-2-
CC butanone 4-phosphate. This is the penultimate step in the biosynthesis
CC of riboflavin. {ECO:0000256|ARBA:ARBA00058151, ECO:0000256|HAMAP-
CC Rule:MF_00178}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=(2S)-2-hydroxy-3-oxobutyl phosphate + 5-amino-6-(D-
CC ribitylamino)uracil = 6,7-dimethyl-8-(1-D-ribityl)lumazine +
CC phosphate + 2 H2O + H(+); Xref=Rhea:RHEA:26152, ChEBI:CHEBI:15377,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:15934, ChEBI:CHEBI:43474,
CC ChEBI:CHEBI:58201, ChEBI:CHEBI:58830; EC=2.5.1.78;
CC Evidence={ECO:0000256|ARBA:ARBA00048785, ECO:0000256|HAMAP-
CC Rule:MF_00178};
CC -!- PATHWAY: Cofactor biosynthesis; riboflavin biosynthesis; riboflavin
CC from 2-hydroxy-3-oxobutyl phosphate and 5-amino-6-(D-
CC ribitylamino)uracil: step 1/2. {ECO:0000256|ARBA:ARBA00004917,
CC ECO:0000256|HAMAP-Rule:MF_00178}.
CC -!- SIMILARITY: Belongs to the DMRL synthase family.
CC {ECO:0000256|ARBA:ARBA00007424, ECO:0000256|HAMAP-Rule:MF_00178}.
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DR EMBL; FWXF01000002; SMC19645.1; -; Genomic_DNA.
DR RefSeq; WP_084056387.1; NZ_FWXF01000002.1.
DR AlphaFoldDB; A0A1W1X6T2; -.
DR STRING; 1121390.SAMN02746041_00740; -.
DR OrthoDB; 9809709at2; -.
DR UniPathway; UPA00275; UER00404.
DR Proteomes; UP000192783; Unassembled WGS sequence.
DR GO; GO:0005829; C:cytosol; IEA:TreeGrafter.
DR GO; GO:0009349; C:riboflavin synthase complex; IEA:UniProtKB-UniRule.
DR GO; GO:0000906; F:6,7-dimethyl-8-ribityllumazine synthase activity; IEA:UniProtKB-UniRule.
DR GO; GO:0009231; P:riboflavin biosynthetic process; IEA:UniProtKB-UniRule.
DR CDD; cd09209; Lumazine_synthase-I; 1.
DR FunFam; 3.40.50.960:FF:000001; 6,7-dimethyl-8-ribityllumazine synthase; 1.
DR Gene3D; 3.40.50.960; Lumazine/riboflavin synthase; 1.
DR HAMAP; MF_00178; Lumazine_synth; 1.
DR InterPro; IPR034964; LS.
DR InterPro; IPR002180; LS/RS.
DR InterPro; IPR036467; LS/RS_sf.
DR NCBIfam; TIGR00114; lumazine-synth; 1.
DR NCBIfam; NF000812; PRK00061.1-4; 1.
DR PANTHER; PTHR21058:SF0; 6,7-DIMETHYL-8-RIBITYLLUMAZINE SYNTHASE; 1.
DR PANTHER; PTHR21058; 6,7-DIMETHYL-8-RIBITYLLUMAZINE SYNTHASE DMRL SYNTHASE LUMAZINE SYNTHASE; 1.
DR Pfam; PF00885; DMRL_synthase; 1.
DR SUPFAM; SSF52121; Lumazine synthase; 1.
PE 3: Inferred from homology;
KW Reference proteome {ECO:0000313|Proteomes:UP000192783};
KW Riboflavin biosynthesis {ECO:0000256|ARBA:ARBA00022619, ECO:0000256|HAMAP-
KW Rule:MF_00178};
KW Transferase {ECO:0000256|ARBA:ARBA00022679, ECO:0000256|HAMAP-
KW Rule:MF_00178}.
FT ACT_SITE 88
FT /note="Proton donor"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00178"
FT BINDING 22
FT /ligand="5-amino-6-(D-ribitylamino)uracil"
FT /ligand_id="ChEBI:CHEBI:15934"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00178"
FT BINDING 56..58
FT /ligand="5-amino-6-(D-ribitylamino)uracil"
FT /ligand_id="ChEBI:CHEBI:15934"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00178"
FT BINDING 80..82
FT /ligand="5-amino-6-(D-ribitylamino)uracil"
FT /ligand_id="ChEBI:CHEBI:15934"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00178"
FT BINDING 85..86
FT /ligand="(2S)-2-hydroxy-3-oxobutyl phosphate"
FT /ligand_id="ChEBI:CHEBI:58830"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00178"
FT BINDING 113
FT /ligand="5-amino-6-(D-ribitylamino)uracil"
FT /ligand_id="ChEBI:CHEBI:15934"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00178"
FT BINDING 127
FT /ligand="(2S)-2-hydroxy-3-oxobutyl phosphate"
FT /ligand_id="ChEBI:CHEBI:58830"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00178"
SQ SEQUENCE 153 AA; 16090 MW; 26B8787B52BB007B CRC64;
MRVFEGNLRA EGLKFGIVVS RFNDFICERL LGGAVDALTR TGASEADIHV YKVPGAFEIP
LTAKKVAASG RYDAIICLGA VIRGATPHFD YVAAEVSKGI ATVSLEAATP ITFGVLTTDT
LEQAIERAGS KAGNKGFEAA MAAVEMANLL KNI
//
