title: Yersiniabactin synthetase: a four-protein assembly line producing the nonribosomal peptide/polyketide hybrid siderophore of Yersinia pestis.
abstract: Yersiniabactin synthetase comprises four proteins, YbtE, HMWP1, HMWP2, and YbtU, encompassing seventeen functional domains, twelve catalytic and five carrier, to select, activate, and incorporate salicylate, three cysteines, and one malonyl moiety into the iron chelator yersiniabactin (Ybt). In the present study, yersiniabactin has been reconstituted in vitro from the 4 protein assembly line by the use of eight biosynthetic precursors. The rate of one turnover, comprising 22 chemical operations performed by the assembly line to release the completed Ybt molecule, was determined at 1.4 min(-1). During the course of Ybt production, the elongating acyl-S-enzyme chain was shown to transfer across a nonribosomal peptide synthetase/polyketide synthase (NRPS/PKS) interprotein interface and then a PKS/NRPS intraprotein interface. This study on the Ybt synthetase assembly line represents the first complete in vitro reconstitution of a nonribosomal peptide/polyketide hybrid system.
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: Deborah Ann
authors.initials: DA
authors.lastname: Miller
authors.forename: Lusong
authors.initials: L
authors.lastname: Luo
authors.forename: Nathan
authors.initials: N
authors.lastname: Hillson
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Keating
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Walsh
mesh_terms: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry; D033862:Iron-Binding Proteins; D009097:Multienzyme Complexes / Q000096:biosynthesis* / Q000737:chemistry; D010453:Peptide Synthases / Q000096:biosynthesis* / Q000737:chemistry; D033902:Periplasmic Binding Proteins; D015202:Protein Engineering; D017262:Siderophores / Q000096:biosynthesis* / Q000737:chemistry; D015010:Yersinia pestis / Q000201:enzymology*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D033862:Iron-Binding Proteins; D009097:Multienzyme Complexes; D033902:Periplasmic Binding Proteins; D017262:Siderophores; C412370:YbtT protein, Yersinia pestis; C412369:YbtU protein, Yersinia pestis; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase