Abstract: Lambda phages that can be used to introduce recombineering functions into host cells are disclosed. Also disclosed are plasmids that can be used to confer recombineering functions to a variety of strains of E. coli and to other bacteria, including Salmonella, Pseudomonas, Cyanobacteria, Spirochaetes. These plasmids and phages can be isolated in vitro and can be used to transform bacterial cells, such as gram negative bacteria.

Abstract: Methods are disclosed herein for inducing homologous recombination in a host cell comprising a target nucleic acid, using a single-stranded nucleic acid molecule. The single-stranded nucleic acid molecule has a sufficient number of nucleotides homologous to the target nucleic acid to enable homologous recombination with the target nucleic acid. The host cell includes a de-repressible promoter operably linked to a nucleic acid encoding a single-stranded binding protein and is deficient for mismatch repair. Isolated host cells of use in this method are also disclosed.

Abstract: This invention provides for improved means to produce binding specific proteins using concatamers of semi-randomly generated oligonucleotides inserted into genes encoding the external domains of bacterial outer membrane proteins. The genes are induced to express and the bacteria are then screened for the ability to bind to predetermined compositions. Those clones carrying the desired binding protein are isolated, cultured and the protein purified. Increased avidity of the binding specific proteins are achieved by reisolating the oligonucleotides which conferred binding affinity and mixing them with new semi-randomly generated oligonucleotides to generate a population enriched for oligonucleotides that had previously conferred to bacteria the desired binding affinity.