[Structure of the nucleosome chain. II. Hydrodynamic models of oligonucleosomes].

Theoretical analysis of the dependencies of sedimentation coefficients of oligonucleosomes on the number of nucleosomes in the chain presented in the first part of the work has been carried out. The analysis has shown that the oligonucleosomes with H1 at mu 0.01 may be described by the model of a short cylinder with ML = 2600 dalton/A and d = 90 A. Oligonucleosomes without H1 at mu 0.01 can be described by the model of a wormlike chain with ML = 880 dalton/A and d = 70 A. In 0.15 M NaCl the oligonucleosome chain without H1 folds up to a compact configuration typical of oligonucleosomes with H1 at mu 0.01. Further compaction of oligonucleosomes with H1 in 0.15 M NaCl results in the formation of a supercoiled structure, whose stable conformation is accounted for by cooperative interactions of at least 5 nucleosomes.