Neither absence nor excess of lambda O initiator-digesting ClpXP protease affects lambda plasmid or phage replication in Escherichia coli.
Owing to rapid proteolysis of the coliphage lambda-coded initiator protein, lambda O, this protein is considered to carry a rate-limiting step in lambda DNA replication. The discovery of ClpXP protease responsible for lambda O protein turnover allowed an opportunity to verify this hypothesis. However, neither absence nor excess of this protease significantly affected the transformation efficiency and copy number of lambda plasmid, or the kinetics of the lambda phage growth. These results are also incompatible with the hypothesis that the stabilization of lambda O plays a role in the switch from early (circle-to-circle) to late (rolling-circle) lambda phage DNA replication. Transcriptional activation of ori lambda, probably assisted by the Escherichia coli DnaA function, remains as the possible rate-limiting step in lambda DNA replication.
Szalewska
A
A
Department of Molecular Biology, University of Gdańsk, Poland.
Wegrzyn
G
G
Taylor
K
K
D049069:ATP-Dependent Proteases; D000074183:ATPases Associated with Diverse Cellular Activities; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D010582:Bacteriophage lambda / Q000378:metabolism* / Q000502:physiology*; D004261:DNA Replication; D004279:DNA, Viral / Q000378:metabolism; D049071:Endopeptidase Clp; D004926:Escherichia coli / Q000201:enzymology* / Q000821:virology; D029968:Escherichia coli Proteins; D015967:Gene Expression Regulation, Viral; D006360:Heat-Shock Proteins / Q000378:metabolism*; D008957:Models, Genetic; D018832:Molecular Chaperones; D010957:Plasmids; D012697:Serine Endopeptidases / Q000378:metabolism*; D014764:Viral Proteins / Q000378:metabolism*; D014779:Virus Replication
D001426:Bacterial Proteins; D004279:DNA, Viral; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; C027812:O protein, Bacteriophage lambda; D014764:Viral Proteins; D049069:ATP-Dependent Proteases; D012697:Serine Endopeptidases; D049071:Endopeptidase Clp; D000251:Adenosine Triphosphatases; C088072:ClpX protein, E coli; D000074183:ATPases Associated with Diverse Cellular Activities