Regulation of riboflavin biosynthesis and transport genes in bacteria by transcriptional and translational attenuation

Nucleic Acids Res. 2002 Jul 15;30(14):3141-51. doi: 10.1093/nar/gkf433.


The riboflavin biosynthesis in bacteria was analyzed using comparative analysis of genes, operons and regulatory elements. A model for regulation based on formation of alternative RNA structures involving the RFN elements is suggested. In Gram-positive bacteria including actinomycetes, Thermotoga, Thermus and Deinococcus, the riboflavin metabolism and transport genes are predicted to be regulated by transcriptional attenuation, whereas in most Gram-negative bacteria, the riboflavin biosynthesis genes seem to be regulated on the level of translation initiation. Several new candidate riboflavin transporters were identified (impX in Desulfitobacterium halfniense and Fusobacterium nucleatum; pnuX in several actinomycetes, including some Corynebacterium species and Strepto myces coelicolor; rfnT in Rhizobiaceae). Traces of a number of likely horizontal transfer events were found: the complete riboflavin operon with the upstream regulatory element was transferred to Haemophilus influenzae and Actinobacillus pleuropneumoniae from some Gram-positive bacterium; non-regulated riboflavin operon in Pyrococcus furiousus was likely transferred from Thermotoga; and the RFN element was inserted into the riboflavin operon of Pseudomonas aeruginosa from some other Pseudomonas species, where it had regulated the ribH2 gene.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / genetics*
  • Bacteria / metabolism
  • Base Sequence
  • Biological Transport / genetics
  • Gene Expression Regulation, Bacterial*
  • Genes, Bacterial / genetics
  • Genome, Bacterial
  • Molecular Sequence Data
  • Multienzyme Complexes / genetics
  • Multienzyme Complexes / metabolism
  • Nucleic Acid Conformation
  • Operon / genetics
  • Phylogeny
  • Protein Biosynthesis
  • RNA, Bacterial / chemistry
  • RNA, Bacterial / genetics
  • Regulatory Sequences, Nucleic Acid / genetics
  • Riboflavin / biosynthesis*
  • Riboflavin / metabolism
  • Riboflavin Synthase / genetics
  • Riboflavin Synthase / metabolism
  • Sequence Homology, Nucleic Acid
  • Transcription, Genetic


  • Multienzyme Complexes
  • RNA, Bacterial
  • 6,7-dimethyl-8-ribityllumazine synthase
  • Riboflavin Synthase
  • Riboflavin