Transduction of Gal+ by coliphage T1. I. Role of hybrids of bacterial and prophage lambda deoxyribonucleic acid.

Hybrids of lambda 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 lambda compared to immune strains. The enhanced transduction was dependent on a functional recA(+) gene in the recipient. Mutations of the donor's lambda 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(lambda). In addition to the effect of lambda immunity in blocking enhanced transduction, mutations of the N gene of the donor's lambda 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 (lambda-gal)T1.