How many base-pairs per turn does DNA have in solution and in chromatin? An answer from wide-angle X-ray scattering
Damaschun, G.; Damaschun, H.; Misselwitz, R.; Pospelov, V.A.; Zalenskaya, I.A.; Zirwer, D.; Müller, J.J.; Vorobev, V.I.
Biomedica Biochimica Acta 42(6): 697-703
1983
ISSN/ISBN: 0232-766X PMID: 6639645 Document Number: 198140
Experimental excess wide-angle X-ray scattering curves from DNA in solution, from Na-DNA crystallites in mother-liquor, from mononucleosomes in solution and from nucleosome core histone complexes are compared with each other and with calculated excess scattering curves of DNA with variable number of base-pairs per turn. The DNA in the Na-DNA crystallites and in the mononucleosomes has on average the canonical B-conformation which is well-known from fibre-diagrams with 10 base-pairs per turn and a rise of 0.34 nm per base-pair. The averaged structure of DNA in solution differs from this conformation. The model which fits best this structure has 10.8 base-pairs per turn and a rise of 0.34 nm per base-pair.