Replication of the linear chromosomal DNA from the centrally located oriC of Streptomyces ambofaciens revealed by PFGE gene dosage analysis.
From a cosmid clone of Streptomyces ambofaciens containing the dnaA and gyrAB genes, a 2.7-kb self-replicating DNA fragment containing the chromosome replication origin oriC was isolated. This cosmid was previously maped physically to a region near the middle of the 8-Mb linear chromosomal DNA. A pulsed-field gel electrophoresis time-course analysis revealed that sequences flanking oriC were overrepresented relative to the rest of the chromosomal DNA during rapid growth, indicating that this origin is active. In addition, the terminal regions of the chromosomal DNA showed a slight overrepresentation at the onset of stationary phase.
Laboratoire de Génétique et Microbiologie, Unité associée INRA 952, Faculté des Sciences, Université Henri Poincaré, Nancy 1, France.
G
G
Fischer
A C
AC
Holl
J N
JN
Volff
D
D
Vandewiele
B
B
Decaris
P
P
Leblond
D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D003360:Cosmids / Q000737:chemistry; D004261:DNA Replication / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics*; D003720:Densitometry; D016521:Electrophoresis, Gel, Pulsed-Field; D018274:Electroporation; D018628:Gene Dosage; D015723:Gene Library; D008969:Molecular Sequence Data; D018741:Replication Origin / Q000235:genetics*; D015183:Restriction Mapping; D013302:Streptomyces / Q000235:genetics*; D013997:Time Factors
D004269:DNA, Bacterial