||Bacteria Escherichia coli
||X. Sunney Xie, Paul J. Choi, Gene-Wei Li, Nam Ki Lee, and Giuseppe Lia, 'Single-Molecule Approach to Molecular Biology in Living Bacterial Cells', Annu. Rev. Biophys. 2008. 37: p.419PubMed ID18573089
||Bremer H, Dennis PP. 1996. Modulation of chemical composition and other parameters of the cell by growth rate. In Escherichia coli and Salmonella: Cellular and Molecular Biology, ed. FCNeidhardt,RCurtiss, JL Ingraham,ECCLin,KBLow, et al., pp. 1553–69.Washington,DC: ASM
||P.418 right column 2nd paragraph: "A living cell as a test tube is fundamentally different from the conventional test tubes of molecular biology and analytical chemistry in
several respects. First, many macromolecules exist in low copy numbers in a living bacterial cell. As shown in Table 1, a particular gene has only one copy, or a few copies owing to DNA replication at the later stage of the cell cycle. A particular mRNA has only a few copies owing to the short cellular mRNA lifetime. Although the copy number for a particular protein varies from 1 to 10^4, some important proteins such as transcription factors and DNA polymerases are present at low copy numbers. This necessitates single-molecule sensitivity in single cells." Depnds on growth rate. The shorter the generation time, the more replication forks exist.