Number of DNA core polymerase per cell

Value ~40 copies/cell
Organism Bacteria Escherichia coli
Reference Kelman Z, O'Donnell M. DNA polymerase III holoenzyme: structure and function of a chromosomal replicating machine. Annu Rev Biochem. 1995 64:171-200 p.175 2nd paragraphPubMed ID7574479
Primary Source Maki H, Kornberg A. The polymerase subunit of DNA polymerase III of Escherichia coli. II. Purification of the alpha subunit, devoid of nuclease activities. J Biol Chem. 1985 Oct 25 260(24):12987-92PubMed ID2997151
Comments "Core contains the DNA polymerase and proofreading exonuclease activities (primary source). There are approximately 40 molecules of core in the cell, and therefore only half are assembled into holoenzyme (primary source). The three subunits of core are tightly associated and cannot be resolved short of denaturation. Individual subunits are provided through use of the genes." p.186 bottom line:"...there are only 10-20 molecules of holoenzymes in a cell [ref 4 PMID 6090455],..."
Entered by Uri M
ID 104123