AC MF_00178; DC Protein; auto TR HAMAP; MF_00178; -; 1; level=0 XX Names: Lumazine_synth XX ID RISB DE RecName: Full=6,7-dimethyl-8-ribityllumazine synthase; DE Short=DMRL synthase; DE Short=Lumazine synthase; DE Short=LS; DE EC=2.5.1.78; GN Name=ribH; XX 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. 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 + H(+) + 2 CC H2O + phosphate; 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 -!- PATHWAY: Cofactor biosynthesis; riboflavin biosynthesis; riboflavin CC from 2-hydroxy-3-oxobutyl phosphate and 5-amino-6-(D- CC ribitylamino)uracil: step 1/2. case or or or CC -!- SUBUNIT: Forms an icosahedral capsid composed of 60 subunits, arranged CC as a dodecamer of pentamers. else case CC -!- SUBUNIT: Homopentamer. end case CC -!- SIMILARITY: Belongs to the DMRL synthase family. XX DR Pfam; PF00885; DMRL_synthase; 1; trigger=no DR NCBIfam; TIGR00114; Lumazine-synth; 1; trigger=no XX KW Riboflavin biosynthesis KW Transferase XX GO GO:0000906; F:6,7-dimethyl-8-ribityllumazine synthase activity GO GO:0009231; P:riboflavin biosynthetic process XX FT From: RISB_AQUAE (O66529) FT BINDING 56..58 FT /ligand="5-amino-6-(D-ribitylamino)uracil" FT /ligand_id="ChEBI:CHEBI:15934" FT BINDING 80..82 FT /ligand="5-amino-6-(D-ribitylamino)uracil" FT /ligand_id="ChEBI:CHEBI:15934" FT BINDING 85..86 FT /ligand="(2S)-2-hydroxy-3-oxobutyl phosphate" FT /ligand_id="ChEBI:CHEBI:58830" FT Optional; Condition: [AQSGEDKTN]-[TS] FT ACT_SITE 88 FT /note="Proton donor" FT Condition: [HR] FT BINDING 22 FT /ligand="5-amino-6-(D-ribitylamino)uracil" FT /ligand_id="ChEBI:CHEBI:15934" FT Condition: [FWY] FT BINDING 113 FT /ligand="5-amino-6-(D-ribitylamino)uracil" FT /ligand_id="ChEBI:CHEBI:15934" FT Condition: [FNLSDMYIHV] FT BINDING 127 FT /ligand="(2S)-2-hydroxy-3-oxobutyl phosphate" FT /ligand_id="ChEBI:CHEBI:58830" FT Condition: [RH] XX Size: 133-190; Related: None; Template: P61714; O66529; P11998; P61711; P9WHE9; Q81MB5; Q57DY1; Q986N2; Q983B0; Q8YGH2; Q57751; P66038; Q2YKV1; Q2YNC6; Scope: Bacteria Archaea Fusion: Nter: None Cter: None Duplicate: in BRADU, BRUA2, BRUAB, BRUME, BRUSU, CAUVC, PSESM, RHILO, RHIME, RHOPA Plasmid: None Comments: Lumazine synthase structures are either observed as pentamers, dimers of pentamers or dodecamers of pentamers. XX # Revision 1.37 2023/06/01 //