title: RelA mutation and pBR322 plasmid amplification in amino acid-starved cells of Escherichia coli.
abstract: Plasmid pBR322 is amplified following amino-acid limitation in Escherichia coli relA hosts. In relA+ hosts there was no significant amplification or a much smaller one. Plasmid amplification is due to the relA mutation; when the relA+ allele is transferred into the relA mutant CP79 this strain no longer amplifies plasmid DNA during amino acid starvation. It is concluded that ppGpp is a negative effector of plasmid replication. Amplification is temperature dependent, being maximal at 32 degrees C and negligible at 37 degrees C.
authors.forename: S
authors.initials: S
authors.lastname: Riethdorf
authors.forename: A
authors.initials: A
authors.lastname: Schroeter
authors.forename: M
authors.initials: M
authors.lastname: Hecker
mesh_terms: D000596:Amino Acids / Q000494:pharmacology; D003470:Culture Media; D004926:Escherichia coli / Q000235:genetics*; D005784:Gene Amplification; D005798:Genes, Bacterial; D009154:Mutation; D010957:Plasmids; D013696:Temperature
chemical_list: D000596:Amino Acids; D003470:Culture Media