title: Post-translational isoprenylation of tryptophan.
abstract: Bacillus subtilis and related bacilli produce a post-translationally modified oligopeptide, ComX pheromone, that stimulates natural genetic competence controlled by quorum sensing. The ComX pheromones are formed by geranylation or farnesylation on a tryptophan residue at the 3 position of its indole ring. This results in the formation of a tricyclic structure including, a newly formed five-membered ring, similar to proline. Isoprenylation of ComX to form ComX pheromones is essential for pheromonal activity, and is functionally more crucial than its amino acid sequence. The ComX pheromone is the first example of isoprenoidal modifiations of tryptophan residues in living organisms and post-translational isoprenylation of any amino acid in prokaryotes. Because the presence of geranylated compounds is unusual in primary and secondary metabolites outside the plant kingdom, post-translational geranylation in bacilli is unprecedented in nature.
authors.affiliation: Department of Chemistry, Graduate School of Science, Tohoku University, Aooba-ku, Sendai, Japan. okada@isc.chubu.ac.jp
authors.forename: Masahiro
authors.initials: M
authors.lastname: Okada
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010675:Pheromones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017368:Protein Prenylation; D053038:Quorum Sensing; D016415:Sequence Alignment; D014364:Tryptophan / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; C087040:ComX protein, Bacillus subtilis; D008565:Membrane Proteins; D010675:Pheromones; D014364:Tryptophan