Cosmid cloning and transposon mutagenesis in Salmonella typhimurium using phage lambda vehicles.

We have constructed a strain of Salmonella typhimurium which contains the malB region from Escherichia coli and carries the bacteriophage lambda receptor protein in its outer membrane. Phage lambda adsorbs to this strain but cannot grow, thus providing a very useful system for transposon mutagenesis of S. typhimurium using lambda vehicles carrying transposons. This system can also be used for cosmid cloning.