The biological activity of bacteriophage DNA, prepared by the cationic detergent dilution technique

Abstract The preparation of phage lambda DNA infecting E. coli K 12 with cationic detergent is described. This DNA infects E. coli spheroblasts with the same efficiency as DNA prepared by phenol methods.

Fractionated precipitation of acid macropolyanions by dialysis, a simple method for the estimation of DNA in complex biological samples.

Abstract After efficient extraction by para-aminosalicylate, (hopping, grinding and eventual sonication, the macropolyanions are transformed into their cetyltrimethylammonium salts. These have differing solubilities, strongly depending on ionic strength. The cationic detergent-macropolyanionic salts are solubilized by high salt concentration. Salt is then dialysed out, rendering the polyanions highly insoluble in a sequential fashion. The insolubilized components are determined quantitatively by monitoring turbidity, which in case of DNA is strictly proportionate to its concentration. This relation is not affected by other components. This makes DNA determination possible even in crude aque…

The Separation of High and Low Molecular Weight RNA by Precipitation with N-Cetyl- N,N,N-trimethyl-ammoniumbromide

Abstract RNA with a sedimentation constant of 28S and 18S can easily be separated from 4S and 5S RNA. The method depends on the different solubulities of nucleic acids in solutions of the cationic detergent N-cetyl-N,N,N-trimethyl-ammoniumbromide at various ionic strengths. The separation can be achieved with high efficiency in one step.

The use of high-pressure liquid cation-exchange chromatography for determination of the 5-methylcytosine content of DNA.