title: Structural biology of the Gram-negative bacterial conjugation systems.
abstract: Conjugation, the process by which plasmid DNA is transferred from one bacterium to another, is mediated by type IV secretion systems (T4SSs). T4SSs are versatile systems that can transport not only DNA, but also toxins and effector proteins. Conjugative T4SSs comprise 12 proteins named VirB1-11 and VirD4 that assemble into a large membrane-spanning exporting machine. Before being transported, the DNA substrate is first processed on the cytoplasmic side by a complex called the relaxosome. The substrate is then targeted to the T4SS for export into a recipient cell. In this review, we describe the recent progress made in the structural biology of both the relaxosome and the T4SS.
authors.affiliation: Institute of Structural and Molecular Biology, UCL and Birkbeck, Malet Street, London, WC1E 7HX, UK.
authors.forename: Aravindan
authors.initials: A
authors.lastname: Ilangovan
authors.affiliation: Institute of Structural and Molecular Biology, UCL and Birkbeck, Malet Street, London, WC1E 7HX, UK.
authors.forename: Sarah
authors.initials: S
authors.lastname: Connery
authors.affiliation: Institute of Structural and Molecular Biology, UCL and Birkbeck, Malet Street, London, WC1E 7HX, UK. Electronic address: g.waksman@ucl.ac.uk.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Waksman
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism*; D003227:Conjugation, Genetic; D004269:DNA, Bacterial / Q000378:metabolism; D006090:Gram-Negative Bacteria / Q000235:genetics* / Q000378:metabolism; D008958:Models, Molecular; D010957:Plasmids; D000069319:Type IV Secretion Systems / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D000069319:Type IV Secretion Systems
keywords: DNA transport; T4SS; Type IV secretion system; bacterial conjugation; structural biology; substrate secretion