B-Z conformational transition and hydration of poly (dC-dG).poly (dC-dG) in fibres

• Published in: International journal of biological macromolecules Vol. 14; no. 3; pp. 161 - 165
• Main Authors: Albiser, G., Prémilat, S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.1992; Elsevier Science
• Subjects: Analytical, structural and metabolic biochemistry; B-Z helical transition; Biological and medical sciences; Chemical Phenomena; Chemistry, Physical; Dna, deoxyribonucleoproteins; fibre dimensions; Fundamental and applied biological sciences. Psychology; hydration; Molecular Conformation; Nucleic acids; poly(dC-dG).poly(dC-dG); Polydeoxyribonucleotides - chemistry; Water; X-Ray Diffraction; fibre dimensions; X-ray diffraction; poly(dC-dG).poly(dC-dG); hydration; B-Z helical transition; Deoxyguanosine; Polynucleotide; Deoxycytidine; Hydration; DNA; X ray diffraction; Conformation; Conformational transition
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/S0141-8130(05)80006-6

The B-Z transition of poly(dC-dG).poly(dC-dG) has been studied by fibre X-ray diffraction and measurement of fibre dimensions. The polymorphism of the Z form is well observed as a function of variations of the r.h. (relative humidity). The Z to B transition is obtained at very high r.h. values. The cooperative transition from B to Z is associated with a disorganization of the fibre. Details about the hydration of the polynucleotide during conformational transitions are presented and it is shown that a nucleotide in Z form can be associated with up to 16 water molecules and up to 22 when in the B form.