TRANSDUCTIONAL INSTABILITY OF Tn5-INDUCED MUTATIONS: GENERALIZED AND SPECIALIZED TRANSDUCTION OF Tn5 BY BACTERIOPHAGE P1

Claire M. Berg ¹, Carmen A. Grullón ¹, Aoquan Wang ¹, William A. Whalen ¹, and Douglas E. Berg ²

¹ Biological Sciences Group (Box U-131), The University of Connecticut, Storrs, Connecticut 06268
² Department of Microbiology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110

Generalized transduction is commonly used to move transposon-induced mutations among bacterial strains by selecting for inheritance of a transposonencoded resistance determinant. Although complete cotransduction of the resistance determinant and the chromosomal mutation might be expected, it is often found that when Tn5(Kan) insertion mutations are transduced by bacteriophage P1 most of the nonmutant kanamycin-resistant transductants are due to specialized transduction of Tn5. Such P1::Tn5 specialized transducing phage are not found when a mutant Tn5 element lacking a functional transposase is employed.