This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Bacher, A Articles by Mailänder, B Search for Related Content PubMed PubMed Citation Articles by Bacher, A Articles by Mailänder, B

Biosynthesis of riboflavin in Bacillus subtilis: function and genetic control of the riboflavin synthase complex.

ABSTRACT

Two riboflavin synthase activities (heavy and light) have been observed in earlier studies with Bacillus subtilis. The heavy enzyme is a complex of one molecule of light enzyme (consisting of three alpha subunits) and approximately 60 beta subunits (A. Bacher, R. Bauer, U. Eggers, H. Harders, and H. Schnepple, p. 729--732, in T. P. Singer (ed.), Flavins and Flavoproteins, Elsevier, Amsterdam, 1976). The formation of alpha and beta subunits is coordinately controlled. Mutants apparently deficient in beta subunits were isolated as riboflavin requires after mutagenesis of B. subtilis with ICR 191. The mutants could grow with diacetyl instead of riboflavin. Growth with diacetyl was associated with the accumulation of substantial amounts of the riboflavin precursor, 6,7-dimethyl-8-(D-ribityl)lumazine. It follows that the mutants are deficient in an enzyme activity required for the formation of the lumazine from the pyrimidine precursor. We conclude that heavy riboflavin synthase is a bifunctional enzyme. The riboflavin synthase activity is mediated by the alpha subunits, whereas the beta subunits are necessary for an earlier biosynthetic step.

This article has been cited by other articles:

• Ramsperger, A., Augustin, M., Schott, A.-K., Gerhardt, S., Krojer, T., Eisenreich, W., Illarionov, B., Cushman, M., Bacher, A., Huber, R., Fischer, M. (2006). Crystal Structure of an Archaeal Pentameric Riboflavin Synthase in Complex with a Substrate Analog Inhibitor: STEREOCHEMICAL IMPLICATIONS. J. Biol. Chem. 281: 1224-1232 [Abstract] [Full Text]  
• Kis, K., Bacher, A. (1995). Substrate Channeling in the Lumazine Synthase/Riboflavin Synthase Complex of Bacillus subtilis. J. Biol. Chem. 270: 16788-16795 [Abstract] [Full Text]