Polarization of the Escherichia coli chromosome. A view from the terminus.
The E. coli chromosome replication arms are polarized by motifs such as RRNAGGGS oligomers, found preferentially on leading strands. Their skew increases regularly from the origin to dif (the site in the center of the terminus where chromosome dimer resolution occurs), to reach a value of 90% near dif. Convergent information indicates that polarization in opposite directions from the dif region controls tightly the activity of dif, probably by orienting mobilization of the terminus at cell division. Another example of polarization is the presence, in the region peripheral to the terminus, of small non-divisible zones whose inversion interferes with spatial separation of sister nucleoids. The two phenomena may contribute to the organization of the Ter macrodomain.
Capiaux
H
H
Laboratoire de Microbiologie et de Génétique moléculaires du CNRS, 118, route de Narbonne, 31320 Toulouse cedex, France.
Cornet
F
F
Corre
J
J
Guijo
M I
MI
Pérals
K
K
Rebollo
J E
JE
Louarn
J M
JM
D020816:Amino Acid Motifs / Q000502:physiology; D001665:Binding Sites; D007446:Chromosome Inversion; D002876:Chromosomes, Bacterial; D004261:DNA Replication; D004269:DNA, Bacterial / Q000378:metabolism*; D004270:DNA, Circular / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics*; D008565:Membrane Proteins / Q000378:metabolism; D008957:Models, Genetic; D011485:Protein Binding
D004269:DNA, Bacterial; D004270:DNA, Circular; D008565:Membrane Proteins