title: PI factor, a novel type quorum-sensing inducer elicits pimaricin production in Streptomyces natalensis.
abstract: A chemically novel autoinducer (PI factor) has been purified from cultures of the pimaricin producer Streptomyces natalensis ATCC27448. The chemical structure of the PI molecule was identified as 2,3-diamino-2,3-bis (hydroxymethyl)-1,4-butanediol. Pimaricin biosynthesis in S. natalensis npi287, a mutant impaired in pimaricin production, was restored by supplementation with either A-factor from Streptomyces griseus IFO13350 or with PI factor. S. natalensis did not synthesize A-factor. The PI autoinducer was active at very low concentrations (50-350 nm). A threshold level of 50 nm was required to observe the induction effect. The dose-response curve was typical of a quorum-sensing type mechanism. The biosynthesis of PI factor was associated with cell growth of S. natalensis, both in defined and complex media. Supplementation of the wild-type S. natalensis with pure PI (300 nm) resulted in a stimulation of 33% of the production of pimaricin. These results indicate that the endogenous synthesis of PI factor is limiting for pimaricin biosynthesis in the wild-type strain. This water-soluble PI factor belongs to a novel class of autoinducers in Streptomyces species different from the classical butyrolactone autoinducers. Because restoration of pimaricin production in the npi287 mutant is conferred by both A-factor and PI factor, S. natalensis appears to be able to integrate different quorum signals from actinomycetes.
authors.affiliation: Instituto de Biotecnología de León, Parque Científico de León, Avda. del Real, n degrees 1, 24006 León, Spain.
authors.forename: Eliseo
authors.initials: E
authors.lastname: Recio
authors.forename: Angel
authors.initials: A
authors.lastname: Colinas
authors.forename: Angel
authors.initials: A
authors.lastname: Rumbero
authors.forename: Jesús F
authors.initials: JF
authors.lastname: Aparicio
authors.forename: Juan F
authors.initials: JF
authors.lastname: Martín
mesh_terms: D000935:Antifungal Agents; D000440:Butanols / Q000378:metabolism; D002082:Butylamines / Q000378:metabolism; D025461:Feedback, Physiological; D015394:Molecular Structure; D010866:Natamycin / Q000096:biosynthesis*; D013302:Streptomyces / Q000378:metabolism*; D014157:Transcription Factors
chemical_list: C492976:2,3-diamino-2,3-bis(hydroxymethyl)-1,4-butanediol; D000935:Antifungal Agents; D000440:Butanols; D002082:Butylamines; D014157:Transcription Factors; D010866:Natamycin