In the previous publication (1) it was reported that deoxyribonucleic acid (DNA) extracted from mycobacteriophage D29 could infect its host, Mycobacterium smegmatis 607. No alteration in the structural integrity of the bacteria such as the production of protoplasts was required; caltures susceptible to intact phage could also be infected with phage D N A .This investigation has been extended to include three additional mycobacteriophages. I n the experiments reported here, D N A extracted from D4 and D32 but not that from D28, was found to be infectious. A t t e m p t s to extend the host range of intact phage with phage D N A were not successful.
Materials and MethodsThe source and preparation of reagents, enzymes, buffers, and chromatography procedures were the same as those described in the preceding publication (1). One additional buffer used in this study, Versonate-potassium trichioroacetate (V-KTCA), Nutrional Biochemicals Company, Cleveland, Ohio, was prepared according to Weil (2). Versonate buffer was composed of 0.2 g disodium Versonate, NaCI 8.0 g, KC1 0.2 g, Na2HPO, 1.15 g, KHdaO4 0.02 g, distilled water to 1000 ml. Potassium trichioroacetate: 0.15 ~, pH 7.6. The final V-KTCA buffer was made up of 1.5 parts Versonate and 2.5 parts potassium trichioroacetate. Compounds not previously described (1), will be noted in the text.Pkages.--D28, D29, D32, and D4 were obtained originally from Dr. Seymour Froman.They were isolated by soil-enrichment techniques and except for D4, are active against certain strains of both virulent and saprophytic acid-fast bacilli; D4 is active against Mycobacterium smegmatis 607 (3, 4). Methods for the production of high-titered lysates and for phage assay have been described (5).Baaeria.--Mycobaaerium smegmatis ATCC 607 (propagating host for D4 and for D29), Mycobacterium sp. ATCC9033 (propagating host for D32), and Mycobacterium sp. ATCC 9626 (propagating host for D28) were employed. These bacteria will be referred to in the text by their ATCC numbers. Two additional species of Mycobacterium were employed in hostrange experiments. They were obtained from Dr. Froman and, according to him, one is M.phlei (F 89) and the other M. smegmalis (F 87). The latter can be distinguished from 607 by its phage susceptibility pattern. These bacteria will be referred to in the text as F 89 and as F 87. Stock cultures were maintained, and log-phase cultures prepared as described (5).