Effect of Diethyl Pyrocarbonate on the Biological Activity of Deoxyribonucleic Acids Isolated from Bacteriophages

Abstract

Summary The biological activity of protein-free transfectious DNA isolated from phage 3NT of Bacillus subtilis was not altered after treatment with diethyl pyrocarbonate (DEP), and the DEP-sodium dodecyl sulphate (SDS) method could be used to extract transfectious DNA from phage 3NT. No transfectious DNA could be isolated from phage T4 of Escherichia coli by the conventional phenol-SDS or by the DEP-SDS method. The DNA extracted from T4 phage either by the phenol-SDS or by the DEP-SDS method had about the same transforming activity, and the transforming activity of T4 DNA extracted by the phenol-SDS method was not reduced by DEP treatment. On the other hand, protein-containing infectious particles obtained from T4 phage of E. coli were inactivated by DEP. It is concluded that DEP does not react with double-stranded phage DNA and can be used in the extraction of biologically active phage DNA, if no protein is needed for biological activity.