The DnaA protein determines the initiation mass of Escherichia coli K-12

TY - JOUR

T1 - The DnaA protein determines the initiation mass of Escherichia coli K-12

AU - Løbner-Olesen, A

AU - Skarstad, K

AU - Hansen, F G

AU - von Meyenburg, K

AU - Boye, E

PY - 1989/6/2

Y1 - 1989/6/2

N2 - DNA replication was studied in a dnaA(Ts) strain containing a plasmid with the dnaA+ gene under plac control. At 42 degrees C, initiation of DNA replication was totally dependent upon the gratuitous inducer isopropyl beta-D-thiogalactopyranoside (IPTG). Flow cytometric measurements showed that at 13% induction of the lac promoter the growth rate, cell size, DNA content, and timing of initiation of DNA replication were indistinguishable from those observed in a wild-type control cell. Higher levels of induction resulted in initiations earlier in the cell cycle and a corresponding increase in the time from initiation to termination. We conclude that the concentration of DnaA protein determines the time of initiation and thereby the initiation mass. With an induction level equal to or above 13%, the synchrony of multiple initiations within one cell was close to that found in a wild-type control cell, showing that a cyclic variation in DnaA content is not necessary for a high degree of synchrony.

AB - DNA replication was studied in a dnaA(Ts) strain containing a plasmid with the dnaA+ gene under plac control. At 42 degrees C, initiation of DNA replication was totally dependent upon the gratuitous inducer isopropyl beta-D-thiogalactopyranoside (IPTG). Flow cytometric measurements showed that at 13% induction of the lac promoter the growth rate, cell size, DNA content, and timing of initiation of DNA replication were indistinguishable from those observed in a wild-type control cell. Higher levels of induction resulted in initiations earlier in the cell cycle and a corresponding increase in the time from initiation to termination. We conclude that the concentration of DnaA protein determines the time of initiation and thereby the initiation mass. With an induction level equal to or above 13%, the synchrony of multiple initiations within one cell was close to that found in a wild-type control cell, showing that a cyclic variation in DnaA content is not necessary for a high degree of synchrony.

KW - Bacterial Proteins/genetics

KW - Cell Cycle

KW - Cell Division

KW - DNA Replication

KW - DNA, Bacterial/analysis

KW - Escherichia coli/cytology

KW - Genes

KW - Genes, Fungal

KW - Kinetics

KW - Models, Theoretical

M3 - Journal article

C2 - 2541928

SN - 0092-8674

VL - 57

SP - 881

EP - 889

JO - Cell

JF - Cell

IS - 5

ER -