Analysis Note

Analyzed by gel electrophoresis and visualization after ethidium bromide staining, with single predominant band of 45 kB or greater.

General description

This is unsheared genomic DNA.

Other Notes

DNA in solution will reanneal on standing at room temperature so it is recommended to boil the solution for 10 minutes and then cool on ice for at least 5 minutes prior to use.

Preparation Note

Purified by equilibrium buoyant density ultracentrifugation in cesium chloride, dialyzed against a solution of 1 mM sodium chloride, 1 mM EDTA and 1 mM Trizma HCl, pH 7.5 and lyophilized at a concentration of approx. 2 units per mL. Approx. 20 A₂₆₀ units per mg DNA. % GC is the percentage of G/C base pairs. T_m is the temperature at the midpoint of the thermal denaturation profile.

Specificity

50% GC; T_m = 90.5 °C

Unit Definition

One unit will yield an A₂₆₀ of 1.0 in 1.0 ml of 1 mM Tris-HCl, pH 7.5, with 1 mM NaCl and 1 mM EDTA (1 cm light path).

Application

The DNAs are particularly useful for genomic analysis, including PCR, library construction in bacteriophage λ, and in heterologous pre-hybridization and hybridization protocols.
Deoxyribonucleic acid sodium salt from Escherichia coli strain B has been used for:
• PCR reactions of genomic DNA of Gardnerella vaginalis
• nick translation and radiolabeling of dNTP
• generating standard curve for 16S rDNA quantification
• transfecting neutrophils
• testing the extraction methods