![]()
Proc Natl Acad Sci U S A 69: 965-9 (1972)[72183805]
Soluble enzyme fractions from uninfected Escherichia coli convert
M13 and PhiX174 viral single strands to their double-stranded
replicative forms. Rifampicin, an inhibitor of RNA polymerase, blocks
conversion of M13 single strands to the replicative forms in vivo and
in vitro. However, rifampicin does not block synthesis of the
replicative forms of PhiX174 either in vivo or in soluble extracts.
The replicative form of M13 synthesized in vitro consists of a
full-length, linear, complementary strand annealed to a viral strand.
The conversion of single strands of M13 to the replicative form
proceeds in two separate stages. The first stage requires enzymes,
ribonucleoside triphosphates, and single-stranded DNA; the reaction
is inhibited by rifampicin. The macromolecular product separated at
this stage supports DNA synthesis with deoxyribonucleoside
triphosphates and a fresh addition of enzymes; ribonucleoside
triphosphates are not required in this second stage nor does
rifampicin inhibit the reaction. We presume that in the first stage
there is synthesis of a short RNA chain, which then primes the
synthesis of a replicative form by a DNA polymerase.
![]()