Gene tandem-mediated selection of coliphage λ-receptive Agrobacterium, Pseudomonas , and Rhizobium strains

Abstract

Agrobacterium, Pseudomonas, and Rhizobium spp. have been made receptive to coliphage .lambda.. To achieve this, recombinant (pTROY) plasmids carrying a constitutive Escherichia coli lamB gene encoding the .lambda. receptor and expressed from an insertion sequence 3 (IS3) promoter were introduced into various bacteria. Because the wild-type .lambda. receptor was not expressed in these bacteria, a procedure called the labB gene tandem protocol was used to select lamB alleles that expressed the .lambda. receptor. This gene tandem protocol may have general use in adapting genes with nonselectable traits to different organisms. Agrobacterium, Pseudomonas, and Rhizobium strains carrying pTROY41613, which encoded a gene tandem-selected .lambda. receptor, could be quantitatively transduced with .lambda. packaged cosmids. With the ability to confer .lambda. receptivity on orgainisms, phage .lambda. now becomes a general DNA delivery agent.