Previous work showed that crossing-over in the middle of the chromosome of phage lambda requires more DNA replication than does crossing-over near the termini. Relocation of cos, the sequence that determines the lambda termini, alters the requirements for replication in a given marked interval, demonstrating that distance from cos determines the amount of DNA replication that is required for ge...

Large amounts of a heat-inducible phage lambda mutant (lambdaCI857) may be obtained under standardized conditions. The phage is harvested by simple polyethylene glycol (C 6000) precipitation and purified by CsCl density gradient banding. Deoxyribonucleic acid (DNA) is extracted by cold phenol and purified by sucrose density gradient sedimentation to yield a homogenous population of unbroken lam...

The assembly of plaque-forming particles in cell-free extracts of induced lambda lysogens was observed two ways. (i) DNA isolated from a lambda-related phage, 434 for example, is added to an extract of an induced lambda lysogen, and plaque-formers with the genotype of the added DNA are detected. (ii) One extract from an induced lambda lysogen that carries an amber mutation in one of the head ge...

Plaque-forming, galactose-transducing lambda strains have been isolated from lysogens in which bacterial genes have been removed from between the galactose operon and the prophage by deletion mutation.-A second class has been isolated starting with a lysogenic strain which carries a deletion of the genes to the right of the galactose operon and part of the prophage. This strain was lysogenized ...

The large subunit of phage lambda terminase, gpA, the gene product of the phage A gene, interacts with the small subunit, gpNul, to form functional terminase. Terminase binds to lambda DNA at cosB to form a binary complex. The terminase:DNA complex binds a prohead to form a ternary complex. Ternary complex formation involves an interaction of the prohead with gpA. The amino terminus of gpA cont...

In order to study mutagenesis in mammalian cells, stable mouse L-cell lines were established with multiple copies of a lambda phage vector that contains the supF gene of Escherichia coli as a target for mutagenesis. Rescue of viable phage from high molecular weight mouse cell DNA using lambda in vitro packaging extracts was efficient (5 phage per microgram of cell DNA per copy) and yielded a ne...

Lambdoid phages are natural relatives of phage lambda. As a group, they are highly polymorphic in DNA sequence and biological specificity. Specificity differences have played a key role in identifying the specific sequences recognized by the N and Q antitermination proteins, the initiator O for DNA synthesis, the terminase system Nv1-A for cutting DNA during packaging, and the cI repressor prot...

The ATP-dependent DNase activity of Escherichia coli disappeared or was markedly reduced after infection with double-stranded DNA phages, T2, T3, T4, T5, T6, T7, lambda, phi80, and P1, but not with the single-stranded DNA phage f1, or the RNA phage Qbeta. This DNase activity was not reduced when chloramphenicol was added prior to phage infection.

Bacteriophage lambda with mutations in genes that control prohead assembly and other head precursors cannot mature their DNA. In this paper we present evidence that the failure of these phage mutants to mature DNA is a reflection of a mechanism that modulates terminase nicking activity during normal phage development. We have constructed plasmids that contain the lambda-cohesive end site (cos) ...