FUNCTION OF GENE-49 OF BACTERIOPHAGE-T4 .1. ISOLATION AND BIOCHEMICAL CHARACTERIZATION OF VERY FAST SEDIMENTING DNA

Very fast-sedimenting DNA was isolated from cells [Escherichia coli] after infection with gene 49 defective phage T4. This DNA appeared membrane bound throughout the time after infection and could be isolated either in the membrane-bound form (M-DNA) or free of membrane (released DNA) depending on the lysis procedure. Released DNA formed complexes of marked stability with sedimentation velocities between 1400S-2100S. These complexes did not seem to contain material other than DNA. This was concluded from the results of RNA, protein and membrane labeling experiments and density analysis. In addition, these complexes were resistant against treatment with n-butanol, phenol, chloroform-methanol, sodium dodecyl sulfate, Sarkosyl, Pronase, RNase or lysozyme. The observation that more than 90% of the purified, very fast-sedimenting DNA is retrapped by Mg-Sarkosyl crystals (M-band) suggests that the M-band technique may not be sufficient as a test for DNA-membrane attachment.