ID RISB_CHLTE Reviewed; 155 AA. AC Q8KAW4; DT 07-JUN-2004, integrated into UniProtKB/Swiss-Prot. DT 01-OCT-2002, sequence version 1. DT 04-NOV-2026, entry version 108. DE RecName: Full=6,7-dimethyl-8-ribityllumazine synthase {ECO:0000255|HAMAP-Rule:MF_00178}; DE Short=DMRL synthase {ECO:0000255|HAMAP-Rule:MF_00178}; DE Short=LS {ECO:0000255|HAMAP-Rule:MF_00178}; DE Short=Lumazine synthase {ECO:0000255|HAMAP-Rule:MF_00178}; DE EC=2.5.1.78 {ECO:0000255|HAMAP-Rule:MF_00178}; GN Name=ribH {ECO:0000255|HAMAP-Rule:MF_00178}; OrderedLocusNames=CT2037; OS Chlorobaculum tepidum (strain ATCC 49652 / DSM 12025 / NBRC 103806 / TLS) OS (Chlorobium tepidum). OC Bacteria; Pseudomonadati; Chlorobiota; Chlorobiia; Chlorobiales; OC Chlorobiaceae; Chlorobaculum. OX NCBI_TaxID=194439; RN [1] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=ATCC 49652 / DSM 12025 / NBRC 103806 / TLS; RX PubMed=12093901; DOI=10.1073/pnas.132181499; RA Eisen J.A., Nelson K.E., Paulsen I.T., Heidelberg J.F., Wu M., Dodson R.J., RA DeBoy R.T., Gwinn M.L., Nelson W.C., Haft D.H., Hickey E.K., Peterson J.D., RA Durkin A.S., Kolonay J.F., Yang F., Holt I.E., Umayam L.A., Mason T.M., RA Brenner M., Shea T.P., Parksey D.S., Nierman W.C., Feldblyum T.V., RA Hansen C.L., Craven M.B., Radune D., Vamathevan J.J., Khouri H.M., RA White O., Gruber T.M., Ketchum K.A., Venter J.C., Tettelin H., Bryant D.A., RA Fraser C.M.; RT "The complete genome sequence of Chlorobium tepidum TLS, a photosynthetic, RT anaerobic, green-sulfur bacterium."; RL Proc. Natl. Acad. Sci. U.S.A. 99:9509-9514(2002). 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:0000255|HAMAP-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:0000255|HAMAP-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:0000255|HAMAP-Rule:MF_00178}. CC -!- SIMILARITY: Belongs to the DMRL synthase family. {ECO:0000255|HAMAP- CC Rule:MF_00178}. 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; AE006470; AAM73254.1; -; Genomic_DNA. DR RefSeq; WP_010933692.1; NC_002932.3. DR AlphaFoldDB; Q8KAW4; -. DR SMR; Q8KAW4; -. DR STRING; 194439.CT2037; -. DR EnsemblBacteria; AAM73254; AAM73254; CT2037. DR KEGG; cte:CT2037; -. DR PATRIC; fig|194439.7.peg.1846; -. DR eggNOG; COG0054; Bacteria. DR HOGENOM; CLU_089358_1_1_10; -. DR OMA; AAAPKNM; -. DR OrthoDB; 9809709at2; -. DR BRENDA; 2.5.1.78; 1345. DR UniPathway; UPA00275; UER00404. DR Proteomes; UP000001007; Chromosome. DR GO; GO:0005829; C:cytosol; IEA:TreeGrafter. DR GO; GO:0009349; C:riboflavin synthase complex; IEA:InterPro. 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; ribH; 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; Riboflavin biosynthesis; Transferase. FT CHAIN 1..155 FT /note="6,7-dimethyl-8-ribityllumazine synthase" FT /id="PRO_0000134740" FT ACT_SITE 90 FT /note="Proton donor" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00178" FT BINDING 24 FT /ligand="5-amino-6-(D-ribitylamino)uracil" FT /ligand_id="ChEBI:CHEBI:15934" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00178" FT BINDING 58..60 FT /ligand="5-amino-6-(D-ribitylamino)uracil" FT /ligand_id="ChEBI:CHEBI:15934" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00178" FT BINDING 82..84 FT /ligand="5-amino-6-(D-ribitylamino)uracil" FT /ligand_id="ChEBI:CHEBI:15934" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00178" FT BINDING 87..88 FT /ligand="(2S)-2-hydroxy-3-oxobutyl phosphate" FT /ligand_id="ChEBI:CHEBI:58830" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00178" FT BINDING 115 FT /ligand="5-amino-6-(D-ribitylamino)uracil" FT /ligand_id="ChEBI:CHEBI:15934" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00178" FT BINDING 129 FT /ligand="(2S)-2-hydroxy-3-oxobutyl phosphate" FT /ligand_id="ChEBI:CHEBI:58830" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00178" SQ SEQUENCE 155 AA; 16308 MW; 912EC24A91BF7675 CRC64; MQVQNIEGSL NASGLKFALV VSRFNDFIGQ KLVEGAIDCI VRHGGSADEI TVIRCPGAFE LPSVTRKAML SGKYDAIVTL GVIIRGSTPH FDVIAAEATK GIAQVGMEAA IPVSFGVLTT ENLEQAIERA GTKAGNKGFD AALAAIEMAN LYKQL //