Nucleic Acids Research, Vol 26, Issue 22 5170-5175, Copyright © 1998 by Oxford University Press
C Margulies and JM Kaguni
The Escherichia coli chromosomal origin contains several bindings sites for
factor for inversion stimulation (FIS), a protein originally identified to
be required for DNA inversion by the Hin and Gin recombinases. The primary
FIS binding site is close to two central DnaA boxes that are bound by DnaA
protein to initiate chromosomal replication. Because of the close proximity
of this FIS site to the two DnaA boxes, we performed in situ footprinting
with 1, 10-phenanthroline- copper of complexes formed with FIS and DnaA
protein that were separated by native gel electrophoresis. These studies
show that the binding of FIS to the primary FIS site did not block the
binding of DnaA protein to DnaA boxes R2 and R3. Also, FIS appeared to be
bound more stably to oriC than DnaA protein, as deduced by its reduced rate
of dissociation from a restriction fragment containing oriC . Under
conditions in which FIS was stably bound to the primary FIS site, it did
not inhibit oriC plasmid replication in reconstituted replication systems.
Inhibition, observed only at high levels of FIS, was due to absorption by
FIS binding of the negative superhelicity of the oriC plasmid that is
essential for the initiation process.
ARTICLES
The FIS protein fails to block the binding of DnaA protein to oriC, the Escherichia coli chromosomal origin
Department of Biochemistry, Michigan State University, East Lansing, MI 48824-1319, USA.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
P. N. Hengen, I. G. Lyakhov, L. E. Stewart, and T. D. Schneider Molecular flip-flops formed by overlapping Fis sites Nucleic Acids Res., November 15, 2003; 31(22): 6663 - 6673. [Abstract] [Full Text] [PDF] |
||||
