title: A transcriptional regulator of a pristinamycin resistance gene in Streptomyces coelicolor.
abstract: Pip is a pristinamycin-induced transcriptional regulator protein detected in many Streptomyces species by its ability to specifically bind sequence motifs within the promoter of a Streptomyces pristinaespiralis multidrug resistance gene (ptr). To investigate the possible role of Pip in regulating multidrug resistance, it was purified from a genetically characterized species, Streptomyces coelicolor, utilizing an affinity matrix of the ptr promoter conjugated to magnetic beads. Reverse genetics identified the corresponding locus and confirmed that it encoded Pip, a protein belonging to the TetR family of procaryotic transcriptional repressors. Pip binding motifs were located upstream of the adjacent gene pep, encoding a major facilitator antiporter homologous to ptr. In vivo analysis of antibiotic susceptibility profiles demonstrated that pep conferred elevated levels of resistance only to pristinamycin I (PI), a streptogramin B antibiotic having clinical importance. Purified recombinant Pip was a dimer (in the presence or absence of PI) and displayed a high affinity for its palindromic binding motifs within the ptr promoter and the upstream region of pep. The Pip/ptr promoter complex was dissociated by PI but not by any of the other nonstreptogramin antibiotics that were described previously as transcriptional inducers. These procaryotic regulatory elements served as the basis for the development of systems allowing repression or induction of cloned genes in mammalian and plant cells in response to streptogramin antibiotics (including pristinamycin, virginiamycin, and Synercid(R)).
authors.affiliation: Biozentrum, University of Basel, Department of Microbiology, Klingelbergstrasse 70, CH-4056 Basel, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Folcher
authors.forename: R P
authors.initials: RP
authors.lastname: Morris
authors.forename: G
authors.initials: G
authors.lastname: Dale
authors.forename: K
authors.initials: K
authors.lastname: Salah-Bey-Hocini
authors.forename: P H
authors.initials: PH
authors.lastname: Viollier
authors.forename: C J
authors.initials: CJ
authors.lastname: Thompson
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins; D001483:Base Sequence; D004352:Drug Resistance, Microbial / Q000235:genetics*; D018432:Drug Resistance, Multiple / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D010453:Peptide Synthases / Q000235:genetics; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000235:genetics; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D013302:Streptomyces / Q000187:drug effects* / Q000235:genetics*; D014158:Transcription, Genetic; D014769:Virginiamycin / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D008565:Membrane Proteins; C418190:Ptr protein, Rhodospirillum centenum; D012097:Repressor Proteins; C034811:tetracycline resistance-encoding transposon repressor protein; D014769:Virginiamycin; D010453:Peptide Synthases; C107614:pipecolate-incorporating enzyme, Streptomyces