title: The orderly, in vitro emergence of DNA from bacteriophage phi29 particles.
abstract: phi29 DNA-containing 12-13- particles (produced by infecting nonsuppressor hosts of Bacillus subtilis with phage containing suppressible mutations in cistrons 12 and 13) can be complemented with lysates containing proteins p12* and p13 to yield infectious phage. Complementation of these particles with lysates containing p12* but not p13 or complementation with purified p12* in the absence of p13 produces a structure (called complex) which has a markedly different organization. Electron microscopy and sedimentation analysis after digestion with DNase I or proteinase K indicate that complex is composed of an intact phage head with a genome-sized linear DNA molecule attached at the collar-tail region. EcoRI digestion establishes that the DNA molecule has a unique orientation. Gel electrophoresis indicates that p12*, the neck appendage protein, is transferred to the particles when complex is formed. Complex can also be produced by incubation of 12-13- particles at 42 degrees , by incubation at pH 6.0, or by incubation in the presence of 20 mM EDTA. Complex is also formed from DNA-containing 12- particles but to a lesser extent.
authors.affiliation: Centro de Biología Molecular (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, Canto Blanco, Madrid-34, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Krawiec
authors.forename: F
authors.initials: F
authors.lastname: Jiménez
authors.forename: J A
authors.initials: JA
authors.lastname: García
authors.forename: N
authors.initials: N
authors.lastname: Villanueva
authors.forename: J
authors.initials: J
authors.lastname: Sogo
authors.forename: M
authors.initials: M
authors.lastname: Salas