'One for all scales' methods for plasmid, phagemid and bacteriophage DNAs preparation.

We have established two simple, reliable, economical and time-saving methods, one for plasmid and phagemid DNAs another for bacteriophage DNAs, that can be applied for any desired scale of vector and its recombinant DNAs preparation. The methods require neither toxic chemicals nor expensive enzymes or chemical reagents. In case of the small-scale preparation, the entire procedure can be done in one microfuge tube. The A260/A280 values for isolated DNAs were constantly between 1.60 and 1.85. The isolated plasmid or phagemid DNA can be used for restriction digestion, religation, transformation, construction of deletion mutants, sequencing, PCR and in vitro transcription. The double-stranded and single-stranded phage DNAs prepared from the present method have the quality to serve as good templates for PCR and site-directed mutagenesis experiments.