Transduction of Gal + by Coliphage T1 I. Role of Hybrids of Bacterial and Prophage λ Deoxyribonucleic Acid

Abstract

Hybrids of λ and adjacent bacterial deoxyribonucleic acid carried in T1 particles were able to transduce Gal + with a greatly increased efficiency to strains which were not immune to λ compared to immune strains. The enhanced transduction was dependent on a functional recA + gene in the recipient. Mutations of the donor's λ prophage which abolished the function of either the cI, O, or P genes in the recipients led to a further enhancement of transduction. The rate of transduction of a nonlysogenic recipient such as W3350 by the hybrid particles may be as much as 140 times greater than transduction of the lysogenic recipient W3350(λ). In addition to the effect of λ immunity in blocking enhanced transduction, mutations of the N gene of the donor's λ prophage abolished enhanced transduction. Mutations in the red, int, xis , and Q genes of the donor's prophage had no significant effect on transduction. The hybrids which mediated the enhanced transduction are called (λ- gal )T1.