  The process of compaction of high molecular weight DNA T4 is investigated
directly in a AFM liquid cell. The AFM-images of globules formed by DNA
molecules in the result of compaction in water-alcohol environments at high
izopropanol concentration (80%) are received; it is found that at intermediate
concentration of izopropanol (40-50%) the DNA molecules form partially
compacted formations in which the separate coils of macromolecules twist in
toroidal structures. It is shown using the technique of deconvolution of the
AFM-images that the globule include only one closely packed DNA molecule. The
model of DNA packing is proposed on the basis of AFM experiment.
