Characterization of the temperate bacteriophage phi(adh) and plasmid transduction in Lactobacillus acidophilus ADH
1989
Raya, R.R. | Kleeman, E.G. | Luchansky, J.B. | Klaenhammer, T.R.
Lactobacillus acidophilus ADH is lysogenic and harbors an inducible prophage, phi(adh). Bacteriophage were detected in cell lysates induced by treatment with mitomycin C or UV light. Electron microscopy of lysates revealed phage particles with a hexagonal head (62 nm) and a long, noncontractile, flexible tail (398 nm) ending in at last five short fibers. Phage phi(adh) was classified within Bradley's B1 phage group and the Siphoviridae family. The phi(adh) genome is a linear double-stranded DNA molecule of 41.7 kilobase pairs with cohesvie ends: a physical maop of the phi(adh) genome was constructed. A prophage-cured derivative of strain ADH, designated NCK102, was isolated from cells that survived UV exposure. NCK102 did not exhibit mitomycin C-induced lysis, but broth cultures lysed upon addition of phage. Phage phi(adh) produced clear plaques on NCK102 in media containing 10 mM CaCl2 at pH values between 5.2 and 5.5. A relysogenized derivative (NCK103) of NCK102 was isolated that exhibited mitomycin C-induced lysis and superinfection immunity to phage phi(adh). Hybridization experiments showed that the phi(adh) genome was present in the ADH and NCK103 chromosomes, but absent in NCK102. These results demonstrated classic lytic and lysogenic cycles of replication for the temperate phage phi(adh) induced from L. acidophilus ADH. Phage phi(adh) also mediates transduction of plasmid DNA. Transductants of strain ADH containing pC194, pGK12, pGB354, and pVA797 were detected frequencies in the range of 3.6 X 10-(8) to 8.3 X 10-(10) per PFU. Rearrangements or deletions were not detected in these plasmids as a consequence of transduction. This is the first description of plasmid transduction in the genus Lactobacillus.
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