title: Isolation and structural characterization of capistruin, a lasso peptide predicted from the genome sequence of Burkholderia thailandensis E264.
abstract: Lasso peptides are a structurally unique class of bioactive peptides characterized by a knotted arrangement, where the C-terminus threads through an N-terminal macrolactam ring. Although ribosomally synthesized, only the gene cluster for the best studied lasso peptide MccJ25 from Escherichia coli consisting of the precursor protein McjA and the processing and immunity proteins McjB, McjC, and McjD is known. Through genome mining studies, we have identified homologues of all four proteins in Burkholderia thailandensis E264 and predicted this strain to produce a lasso peptide. Here we report the successful isolation of the predicted peptide, named capistruin. Upon optimization of the fermentation conditions, mass spectrometric and NMR structural studies proved capistruin to adopt a novel lasso fold. Heterologous production of the lasso peptide in Escherichia coli showed that the identified genes are sufficient for the biosynthesis of capistruin, which exhibits antimicrobial activity against closely related Burkholderia and Pseudomonas strains. In general, our rational approach should be widely applicable for the isolation of new lasso peptides to explore their high structural stability and diverse biological activity.
authors.affiliation: Department of Chemistry, Philipps-University Marburg, Hans-Meerwein-Strasse, D-35032 Marburg, Germany.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Knappe
authors.forename: Uwe
authors.initials: U
authors.lastname: Linne
authors.forename: Séverine
authors.initials: S
authors.lastname: Zirah
authors.forename: Sylvie
authors.initials: S
authors.lastname: Rebuffat
authors.forename: Xiulan
authors.initials: X
authors.lastname: Xie
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Marahiel
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development; D001430:Bacteriocins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001483:Base Sequence; D016957:Burkholderia pseudomallei / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics; D005285:Fermentation; D016680:Genome, Bacterial; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D016133:Polymerase Chain Reaction
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D010455:Peptides; C533129:capistruin