Biology Reference
In-Depth Information
Fig. 1.
Theoretical and empirical plots of % mutant RNA yield of infec-
tious virions in
in vitro
assembly assays.
Z
is the total pRNA number per
procapsid varied from 1 to 12, supposing that the minimal number of the
bound mutant pRNA required to block DNA packaging is 1. (Adapted from
Ref. 107, with permission from the author and the publisher, American
Society for Microbiology.)
be plotted and compared to a series of predicted curves to find a best
fit (Fig. 1). In this method, there will be two unknown parameters.
One is the stoichiometry
Z
, and the other is the copy number,
X
, of
mutant that is needed to block the reaction. In the real experiment,
the productive reaction is “dominant” and can be observed, while the
abortive reaction is “recessive” and can only be predicted, but not
observed. Therefore, the equation can be used to determine two
parameters in separate experiments:
Case one
assumes that the stoichiometry,
Z
, is unknown, but the
number,
X
, that is sufficient to block the reaction is one. A series of
curves can then be generated; for example, several curves can be gen-
erated where
Z
varies from 1 to 30 (Fig. 2). Curves of observed
empirical data can then be superimposed onto the predicted curves to
find a match, and thus the stoichiometry can be deduced from the
