The precipitation of DNA by spermine

✍ Scribed by Juan A. Subirana; Juan L. Vives

• Publisher: Wiley (John Wiley & Sons)
• Year: 1981
• Tongue: English
• Weight: 173 KB
• Volume: 20
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1981.360201019

✦ Synopsis

The structure of the complex of DNA and spermine has been studied by x-ray diffracti0n.l In the course of this study it was found that a fibrous precipitate of the complex could be obtained easily under different conditions. It appeared, therefore, of interest to define more precisely the conditions required for precipitation. In related studies, Gosule and S ~h e l l m a n ~, ~ have shown that the addition of spermine to a dilute solution of T7 DNA causes an alteration of the shape of the DNA molecule to a condensed form. This condensation might be equivalent to the formation of a fibrous precipitate in more concentrated DNA solutions. In fact, the results we present here show that both phenomena occur under the same ionic conditions, so that the condensation of T7 DNA can be considered as a microprecipitation.