[Simple method for isolation of three DNA-polymerases from E. coli using chromatography on DNA-cellulose]

A simple method for isolation of three DNA-polymerases from E. coli is developed; it is based on properties of the enzymes to bind with single-stranded DNA, fixed on cellulose. DNA-polymerases I, II and III were identified by their relation to templates, ionic strength, heat denaturation and inhibition of the activity with agents which blocked sulfhydryl groups. After purification which included chromatography on DNA-cellulose as well as fractionation with phosphocellulose and gel-filtration through Sephadex G-100, the enzymes were free the endonucleases contamination.