We have completed a study of the significance of the single-stranded interruptions for transfection by T5 phage DNA, a collaboration with Lynn Enquist and Ann Skalka concerning the effect of the recB, C nuclease on transfection of E. coli by 20 different forms and genotypes of coliphage DNA, a study on the regulation of protein synthesis in filamentous phage infected E. coli, and are completing an infectious DNA assay for lambda prophage DNA which provides a simple and highly specific assay for the lambda prophage excision protein. We are studying the DNA-binding proteins found in T5 phage-infected E. coli. Our future work is mainly concerned with the application of transfection assays to genetic recombination and genetic surgery in vitro.