Disease relevance of Lumazine

• A library of Photobacterium phosphoreum DNA was screened in lambda 2001 for the lumazine protein gene, using two degenerate 17-mer oligonucleotide probes that were deduced from a partial protein primary sequence [1].
• Considerable sequence similarity was detected between lumazine protein, the yellow fluorescence protein from Vibrio fischeri, and the alpha subunit of riboflavin synthetase (EC 2.5.1.9) [1].
• Substrate channeling in the lumazine synthase/riboflavin synthase complex of Bacillus subtilis [2].
• High order quaternary arrangement confers increased structural stability to Brucella sp. lumazine synthase [3].
• The lumazine synthase/riboflavin synthase complex of Bacillus subtilis consists of an icosahedral capsid of 60 beta subunits surrounding a core of three alpha subunits [2].

High impact information on Lumazine

• A highly conserved sequence in lumazine protein corresponds to the proposed lumazine binding sites in the alpha subunit of riboflavin synthetase [1].
• The fragment contained an open reading frame, encoding a 189-residue protein, that had a predicted amino acid sequence that concurred with the partial sequence determined for lumazine protein [1].
• In all lumazine synthases studied, the topologically equivalent active sites are located at the interfaces between adjacent subunits in the pentameric modules [3].
• Temperature-dependent presteady state kinetics of lumazine synthase from the hyperthermophilic eubacterium Aquifex aeolicus [4].
• The lumazine protein gene in Photobacterium phosphoreum is linked to the lux operon [5].

Chemical compound and disease context of Lumazine

• The lumazine synthase/riboflavin synthase of Bacillus subtilis is a bifunctional enzyme complex catalysing the formation of riboflavin from 5-amino-6-(D-ribitylamino)-2,4(1H,3H)-pyrimidinedione and L-3,4-dihydroxy-2-butanone-4-phosphate via 6,7-dimethyl-8-ribityllumazine [6].
• Spectroscopic investigations of the single tryptophan residue and of riboflavin and 7-oxolumazine bound to lumazine apoprotein from Photobacterium leiognathi [7].
• However, when tested in Tris buffer vs Mycobacterium tuberculosis lumazine synthase, three of the phosphate inhibitors displayed inhibition constants in the 4-5 nM range, indicating that they are much more potent than the parent purinetrione [8].
• 6,7-Dimethyllumazine derivatives, substituted at the 8-position with aldityls or monohydroxyalkyl groups, have been examined for their binding ability to lumazine apo-protein from two strains of Photobacterium phosphoreum using fluorescence dynamics techniques [9].
• The equilibrium association of lumazine protein from Photobacterium phosphoreum with luciferases from either P. phosphoreum or an aldehyde-requiring dark mutant of Vibrio harveyi is measured from changes of the rotational correlation time which is derived from the decay of the lumazine ligand's fluorescence anisotropy [10].

Biological context of Lumazine

• Lumazine synthases have been observed in the form of pentamers, dimers of pentamers, icosahedral capsids consisting of 60 subunits and larger capsids with unknown molecular structure [11].
• This rapid channel of anisotropy loss is attributed to energy transfer from the flavin intermediate bound on the luciferase to the lumazine ligand, reflects the presence of protein-protein complexation, and is greatest in the case of P. leiognathi, but not at all for V. fischeri [12].
• This enzyme and lumazine protein show considerable sequence homology [13].
• The last two steps in the biosynthesis of riboflavin, an essential metabolite that is involved in electron transport, are catalyzed by lumazine synthase and riboflavin synthase [14].
• A high-throughput screening method based on the competitive binding of a lumazine synthase inhibitor and riboflavin to the active site of Schizosaccharomyces pombe lumazine synthase was developed [15].

Associations of Lumazine with other chemical compounds

• 6,7-Dimethyl-8-ribityllumazine synthase (lumazine synthase) catalyses the penultimate step in the biosynthesis of riboflavin [16].
• Shifts of the C(2)-N(3) mode in D2O may arise from hydrogen-bonding changes at C(2)=O in lumazine protein (1284-1291 cm-1), flavodoxin (1300-1280 cm-1), and glucose oxidase (1297-1287 cm-1) [17].
• Thiols successfully displace the lumazine in the molecular probe, which is accompanied by a decrease of the fluorescence [18].
• Fourier transform infrared (FTIR) spectra have been obtained from solution samples of the heterocycles uracil, lumazine, and violapterin and reveal interpretable carbonyl stretching frequencies [19].
• AIMS: To examine the effects of five inhibitors of methanogenesis, 2-bromoethanesulphonate (BES), 3-bromopropanesulphonate (BPS), lumazine, propynoic acid and ethyl 2-butynoate, on CH4 production of the ruminal methanogens Methanobrevibacter ruminantium, Methanosarcina mazei and Methanomicrobium mobile [20].

Gene context of Lumazine

• By expression of P. phosphoreum ribE in E. coli using the bacteriophage T7 promoter-RNA polymerase system, ribE was shown to code for riboflavin synthetase, which catalyzes the conversion of lumazine to riboflavin [21].
• The apoprotein can also bind lumazine derivatives with a quarternary C-7 [13].
• In vitro damage to rat lens by lumazine and xanthine oxidase: prevention by superoxide dismutase [22].

Analytical, diagnostic and therapeutic context of Lumazine

• The lumazine synthase-riboflavin synthase complex of Bacillus subtilis. Crystallization of reconstituted icosahedral beta-subunit capsids [23].
• Single turnover experiments monitored by multiwavelength photometry were performed with the recombinant lumazine synthase of Bacillus subtilis [24].
• Here we describe the analysis of the assembly of native and mutant forms of lumazine synthases from Bacillus subtilis and Aquifex aeolicus at various pH values and in the presence of different buffers using small angle X-ray scattering and electron microscopy [11].
• On three enzyme complexes, lumazine synthase from Bacillus subtilis, proteasome from Thermoplasma acidophilum and GTP cyclohydrolase I from Escherichia coli, the decoration sites as determined by electron microscopy (EM) were correlated with their atomic surface structures as obtained by X-ray crystallography [25].
• Lumazine protein acts as an electronic excited state transducer in bioluminescence of Photobacterium species [13].

References