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1.  Initiation and Termination of Bacterial Deoxyribonucleic Acid Replication in Low Concentrations of Chloramphenicol 
Journal of Bacteriology  1973;113(2):1066-1069.
Escherichia coli 15T− can initiate a cycle of deoxyribonucleic acid replication with equal efficiency in the presence of 25 or 50 μg of chloramphenicol/ml. However, these replication cycles are not completed in the presence of these drug concentrations, and the amount of replication decreases with increasing drug concentration.
PMCID: PMC285329  PMID: 4570592
2.  Relation of the Segregative Origin of Chromosome Replication to the Origin of Replication After Amino Acid Starvation 
Journal of Bacteriology  1969;98(2):536-542.
Cultures of Escherichia coli 15T− and K-12 were labeled with 3H-thymine before, during, and after amino acid starvation. The number of labeled segregating units was measured by autoradiography of microcolonies derived from the labeled cells. In both strains, labels inserted before starvation and during starvation appeared to segregate as if incorporated into the same polynucleotide strands. However, labels inserted during and after starvation segregated as if incorporated into different polynucleotide strands. In view of previous data, it was concluded that replication after amino acid starvation originates from the region of the chromosome which serves as the origin for replication during normal growth and division.
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PMCID: PMC284850  PMID: 4891256
3.  Chromosome Replication in Salmonella typhimurium1 
Journal of Bacteriology  1969;97(2):848-860.
The replication of the Salmonella typhimurium chromosome was studied. As with E. coli 15T−, replication was sequential. After amino acid starvation, replication proceeded from a unique and heritable region of the chromosome. 5-Bromouracil, when substituted for thymine, did not disturb the sequence of replication nor did it initiate extra replication cycles. By labeling the origin and the terminus of the chromosome with 3H- and 14C-thymine, respectively, it was possible to determine that the rate of chain elongation decreases as the growth rate decreases. No gap in the replication cycle could be observed.
PMCID: PMC249769  PMID: 4886297
4.  Segregation of Deoxyribonucleic Acid in Bacteria: Association of the Segregating Unit with the Cell Envelope 
Journal of Bacteriology  1967;94(2):415-421.
Cells of the gram-positive organism Lactobacillus acidophilus R-26 were labeled with 3H-thymine to measure the segregation of radioactive deoxyribonucleic acid (DNA) into daugher cells. Such cells were found to contain 8 conserved units of DNA which would correspond to two replicating chromosomes per cell. Fluorescent antibody (FA) against this organism was used to demonstrate that portions of the cell surface (2 to 4 units per cell) were conserved during growth and division. The permanent association of DNA with these conserved cell surface units was measured by combining autoradiography with FA techniques. DNA synthesized immediately before FA labeling was not associated with the fluorescent cell surface, whereas DNA synthesized a generation previously was. The results are consistent with a model in which DNA becomes permanently fixed to the cell surface when it is first used as a template.
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PMCID: PMC315056  PMID: 4962703

Results 1-5 (5)