@misc{oai:ir.soken.ac.jp:00000879,
author = {尾崎, 美和子 and オザキ, ミワコ and OZAKI, Miwako},
month = {2016-02-17},
note = {During the growth phase transition of Escherichia coli from exponential
growth to stationary phase, the pre-existing RNA polymerase was found to be
converted into at least three different holoenzyme forms, which could be
isolated by phosphocellulose column chromatography (Ozaki, M., et al. (1991)
Mol. Gen. Genet. 230, 17-24). The relative levels of these three holoenzyme
forms changed depending on the phase of cell growth. In the in vitro mixed
transcription assay using 33 different E. coli promoters, one of the
stationary-phase RNA polymerase, S1, showed promoter recognition properties
which are significantly different from that of holoenzyme from exponentially
growing cells.
Enzyme reconstitution experiments showed that the altered promoter
selectivity is due to alteration in core enzyme. After a variety of attempts
to achieve in vitro interconversion between the exponential and the stationary
phase RNA polymerases, S1-form enzyme was found to be converted in vitro into
such an enzyme as the log-phase form, following incubation with nucleotides or
pyrophosphate (Ozaki, M. et al., (1991) Nucleic Acids Res. in press). The
conversion was indicated by not only the shift of elution position from a
phosphocellulose column but also the change in the promoter selectivity. Using
polyphosphate kinase (PPK) which polymerizes the terminal phosphate of ATP to
a long chain polyphosphate in a freely reversible reaction, polyphosphate was
detected in the stationary-phase RNA polymerase (Ozakl, M. et al., in
preparation). These results altogether lead to the possibility that RNA
polymerase is converted into the stationary-phase form by binding
polyphosphate. I propose that the modulation of RNA polymerase by
polyphosphate plays a role in the global switch of gene transcription during
the growth transition of E. coli to stationary phase., 総研大甲第18号},
title = {Structural and Functional Modulations of RNApolymerase During Growth Phase Transition ofEscherichia coli},
year = {}
}