Lambda phages have considerable potential as gene delivery vehicles due to their genetic tractability, low cost, safety and physical characteristics in comparison to other nanocarriers and gene porters. Little is known concerning lambda phage-mediated gene transfer and expression in mammalian hosts. We therefore performed experiments to evaluate lambda-ZAP bacteriophage-mediated gene transfer a...

Bacteriophage lambda (lambda) permits the display of many foreign peptides and proteins on the gpD major coat protein. However, some recombinant derivatives of gpD are incompatible with the assembly of stable phage particles. This presents a limitation to current lambda display systems. Here we describe a novel, plasmid-based expression system in which gpD deficient lambda lysogens can be co-co...

Procedures for increasing both sensitivity and reproducibility of virus production in disrupted DNA-infected cell preparations have been described. A variety of chemical agents and physical procedures, including fractionation by centrifugation, were tested for effects on the ability of disrupted cell preparations to form virus particles. DNA prepared from lambda-virulent phage, a deletion mutan...

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 ...

A class of recombinant phage lambda clones are recovered from human genomic libraries on Escherichia coli recB21 recC22 sbcB15 cells, which fail to form plaques on wild-type cells. We report experiments which address the mechanism of this inhibition. The introduction of the recombination-stimulating sequence chi into one such clone allows growth of this phage on Rec+ cells. In addition, the ins...

Although most of the 73 open reading frames (ORFs) in bacteriophage λ have been investigated intensively, the function of many genes in host-phage interactions remains poorly understood. Using yeast two-hybrid screens of all lambda ORFs for interactions with its host Escherichia coli, we determined a raw data set of 631 host-phage interactions resulting in a set of 62 high-confidence interactio...

A novel phage lambda mutation, called dc10, which interferes with proper lambda head assembly has been isolated and characterized. Phage lambda carrying this mutation is (i) unable to form plaques at 30 or 37 degrees C but does so at 42 degrees C and (ii) unable to form plaques at 42 degrees C on pN-constitutive hosts. Both properties are due to dc10 since all phage revertants for one phenotype...

E. coli cells lysogenic for the thermoinducible prophage lambdacI857 can be transiently induced by a brief heat treatment. Although this treatment does not kill the cells, some lambda products normally formed during vegetative phage development are made that can alter the response of host cells to x-irradiation by causing an increase in radioresistance. This increased resistance is particularly...

The increased prevalence of multidrug-resistant bacterial pathogens motivated us to attempt to enhance the therapeutic efficacy of bacteriophages. The therapeutic application of phages as antibacterial agents was impeded by several factors: (i) the failure to recognize the relatively narrow host range of phages; (ii) the presence of toxins in crude phage lysates; and (iii) a lack of appreciatio...

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...