Purification and properties of a DNA-dependent ATPase induced by bacteriophage T4.

A DNA-dependent ATPase formed after T4 phage infection is purified to apparent homogeneity. The molecular weight of the purified enzyme is 50 000 when determined by glycerol gradient centrifugation and by sodium dodecylsulfate/polyacrylamide gel electrophoresis. The enzyme at an earlier stage in purification (prior to DEAE-cellulose chromatography) exists as a complex with a molecular weight of 100000. However, molecular weight determinations by Sephadex gel chromatography give considerably decreased molecular weights for the complex and for the enzyme after DEAE-cellulose chromatography. The enzyme is stimulated to varying degrees by a variety of single-stranded polydeoxyribonucleotides or by single-stranded DNA, but no chemical change in the polynucleotide has been detected as a result of the enzyme action.