Buoyant density of E. coli DNA in CsCl 7.7M solution

Range 1.709 at 25°C: 1.736 at 80°C g/cm^3
Organism Bacteria Escherichia coli
Reference Bhinyo Panijpan, The buoyant density of DNA and the G + C content, J. Chem. Educ., 1977, 54 (3), p 172 DOI: 10.1021/ed054p172 p.173 right columnPubMed ID838782
Primary Source [7] Tunis.M-J. B..and Hearst, J. E., On the hydration of DNA. I. Preferential hydration and stability of DNA in concentrated trifluoroacetate solution. Biopolymers. 6, 1325 and 1345(1968) [11] Vinograd, J., Greenwald, R., and Hearst.J. E.. Effect of temperature on the buoyant density of bacterial and viral DNA in CsCl solutions in the ultracentrifuge, Biopolymers. 3.109 (1965) DOI: 10.1002/bip.360030201PubMed ID5669470
Comments P.173 right column: "Heating also causes the partial breakdown of DNA hydration shells at temperatures near Tm, e.g., E. coli DNA has a buoyant density of 1.709 at 25°C, which becomes 1.736 at 80°C (primary sources)." The density depends on the GC content. Also the density depends on the solution composition because the amount of hydration affects the density as the hydrated water is part of the mass and volume that derive the density.
Entered by Uri M
ID 107857