INVESTIGADORES
RAYA Raul Ricardo
artículos
Título:
Characterization of the temperate bacteriophage phi adh and plasmid transduction in Lactobacillus acidophilus ADH.
Autor/es:
RAYA RR, KLEEMAN EG, LUCHANSKY JB, KLAENHAMMER TR.
Revista:
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
Editorial:
AMER SOC MICROBIOLOGY
Referencias:
Lugar: Washington, Estados Unidos; Año: 1989 vol. 55 p. 2206 - 2213
ISSN:
0099-2240
Resumen:
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 cohesive ends: a
physical map 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 at 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.