Structural highlights
Function
[RIB4_SCHPO] Catalyzes the formation of 6,7-dimethyl-8-ribityllumazine by condensation of 5-amino-6-(D-ribitylamino)uracil with 3,4-dihydroxy-2-butanone 4-phosphate. This is the penultimate step in the biosynthesis of riboflavin. Also binds riboflavin with an unexpected high affinity.[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The amino acid residue tryptophan 27 of 6,7-dimethyl-8-ribityllumazine synthase of the yeast Schizosaccharomyces pombe was replaced by tyrosine. The structures of the W27Y mutant protein in complex with riboflavin, the substrate analogue 5-nitroso-6-ribitylamino-2,4(1H,3H)-pyrimidinedione, and the product analogue 6-carboxyethyl-7-oxo-8-ribityllumazine, were determined by X-ray crystallography at resolutions of 2.7-2.8 A. Whereas the indole system of W27 forms a coplanar pi-complex with riboflavin, the corresponding phenyl ring in the W27Y mutant establishes only peripheral contact with the heterocyclic ring system of the bound riboflavin. These findings provide an explanation for the absence of the long wavelength shift in optical absorption spectra of riboflavin bound to the mutant enzyme. The structures of the mutants are important tools for the interpretation of the unusual physical properties of riboflavin in complex with lumazine synthase.
Structural basis of charge transfer complex formation by riboflavin bound to 6,7-dimethyl-8-ribityllumazine synthase.,Koch M, Breithaupt C, GerhardtHaase S, Weber S, Cushman M, Huber R, Bacher A, Fischer M Eur J Biochem. 2004 Aug;271(15):3208-14. PMID:15265040[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Fischer M, Haase I, Feicht R, Richter G, Gerhardt S, Changeux JP, Huber R, Bacher A. Biosynthesis of riboflavin: 6,7-dimethyl-8-ribityllumazine synthase of Schizosaccharomyces pombe. Eur J Biochem. 2002 Jan;269(2):519-26. PMID:11856310
- ↑ Koch M, Breithaupt C, GerhardtHaase S, Weber S, Cushman M, Huber R, Bacher A, Fischer M. Structural basis of charge transfer complex formation by riboflavin bound to 6,7-dimethyl-8-ribityllumazine synthase. Eur J Biochem. 2004 Aug;271(15):3208-14. PMID:15265040 doi:10.1111/j.1432-1033.2004.04253.x
