Complementation Studies of Bacteriophage λ O Amber Mutants by Allelic Forms of O Expressed from Plasmid, and O-P Interaction Phenotypes.

λ genes O and P are required for replication initiation from the bacteriophage λ origin site, λ, located within gene . Questions have persisted for years about whether O-defects can indeed be complemented . We show the effect of original null mutations in O and the influence of four origin mutations (three are in-frame deletions and one is a point mutation) on complementation.

Lambda display phage as a mucosal vaccine delivery vehicle for peptide antigens.

Bacteriophage are structurally stable in the gastro-intestinal tract and have favorable traits of safety, stability, ease of production, and immunogenicity. These attributes make them potential candidates as oral vaccine delivery vehicles but little is known about their capacity to induce mucosal immune responses in the small intestine. Whole body imaging of mice confirmed lambda bacteriophage (LP) were distributed throughout the gastro-intestinal tract 24 h after oral delivery.

Lambda gpP-DnaB Helicase Sequestration and gpP-RpoB Associated Effects: On Screens for Auxotrophs, Selection for Rif(R), Toxicity, Mutagenicity, Plasmid Curing.

The bacteriophage lambda replication initiation protein P exhibits a toxic effect on its Escherichia coli (E. coli) host, likely due to the formation of a dead-end P-DnaB complex, sequestering the replicative DnaB helicase from further activity. Intracellular expression of P triggers SOS-independent cellular filamentation and rapidly cures resident ColE1 plasmids.

Phage Lambda P protein: trans-activation, inhibition phenotypes and their suppression.

The initiation of bacteriophage λ replication depends upon interactions between the oriλ DNA site, phage proteins O and P, and E. coli host replication proteins. P exhibits a high affinity for DnaB, the major replicative helicase for unwinding double stranded DNA.

A CI-independent form of replicative inhibition: turn off of early replication of bacteriophage lambda.

Several earlier studies have described an unusual exclusion phenotype exhibited by cells with plasmids carrying a portion of the replication region of phage lambda. Cells exhibiting this inhibition phenotype (IP) prevent the plating of homo-immune and hybrid hetero-immune lambdoid phages. We have attempted to define aspects of IP, and show that it is directed to repλ phages.

Dual expression system for assembling phage lambda display particle (LDP) vaccine to porcine Circovirus 2 (PCV2).

The bacteriophage lambda small capsid protein D forms trimers on the phage head. D-fusion polypeptides can be expressed from plasmids in E. coli and remain soluble without aggregation.

NinR- and red-mediated phage-prophage marker rescue recombination in Escherichia coli: recovery of a nonhomologous immlambda DNA segment by infecting lambdaimm434 phages.

We examined the requirement of lambda recombination functions for marker rescue of cryptic prophage genes within the Escherichia coli chromosome. We infected lysogenic host cells with lambdaimm434 phages and selected for recombinant immlambda phages that had exchanged the imm434 region of the infecting phage for the heterologous 2.6-kb immlambda region from the prophage.