title: The tripartite immunity system of phages P1 and P7.
abstract: Prophages P1 and P7 exist as unit copy DNA plasmids in the bacterial cell. Maintenance of the prophage state requires the continuous expression of two repressors: (i) C1 is a protein which negatively regulates the expression of lytic genes including the C1 inactivator gene coi, and (ii) C4 is an antisense RNA which specifically inhibits the synthesis of an anti-repressor Ant. In addition, C1 repression is strengthened by lxc encoding an auxiliary repressor protein. The repressors C1, C4 and Lxc are components of a tripartite immunity system of the two phages. Here, the mode of action of these regulatory components including their antagonists Coi and Ant is described.
authors.affiliation: Max-Planck-Institut für Molekulare Genetik, Berlin, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Heinrich
authors.forename: M
authors.initials: M
authors.lastname: Velleman
authors.forename: H
authors.initials: H
authors.lastname: Schuster
mesh_terms: D017101:Bacteriophage P1 / Q000276:immunology*; D001435:Bacteriophages / Q000276:immunology*; D001483:Base Sequence; D008969:Molecular Sequence Data; D016372:RNA, Antisense / Q000502:physiology*; D012097:Repressor Proteins / Q000502:physiology*
chemical_list: D016372:RNA, Antisense; D012097:Repressor Proteins