Structural forms, stabilities and transitions in double-helical poly(dG-dC) as a function of hydration and NaCI content. An infrared spectroscopic study
- 1 January 1986
- journal article
- Published by Oxford University Press (OUP) in Nucleic Acids Research
- Vol. 14 (20) , 8167-8182
- https://doi.org/10.1093/nar/14.20.8167
Abstract
The poly(dG-dC) helical duplex forms a modified, B-family structure (B*) at very high hydration and a normal B structure at slightly lower hydration. The B* structure is slightly different in sugar-phosphate and base-stacking conformations than the B structure. Increasing the hydration or decreasing the NaCl content stabilizes B* with respect to B. Poly(dG-dC) forms the Z structure at low NaCl contents when the hydration is sufficiently reduced. At moderate NaCl content, the B to Z transition is sharp and cooperative for hydration with D2O. Hydration with H2O broadens the transition which occurs at lower hydration. This suggests that hydrogen bonding is stronger in the Z structure and helps stabilize Z over B. IR spectra may be used to quantitatively estimate the fractions of B and Z structures present in a sample. Some new indicator bands are described.Keywords
This publication has 20 references indexed in Scilit:
- Vacuum UV CD of the low-salt Z-forms of poly(rG-dC)·poly(rG-dC), and poly(dG-m5dC)·poly(dG-m5dC)Biopolymers, 1986
- New DNA polymorphism: evidence for a low salt, left-handed form of poly(dG-m5dC)Nucleic Acids Research, 1985
- Z-DNA is Formed by poly(dC-dG) and poly (dm5C-dG) at Micro or Nanomolar Concentrations of some Zinc(II) and Copper(II) ComplexesJournal of Biomolecular Structure and Dynamics, 1985
- The infrared spectrum and structure of the type I complex of silver and DNANucleic Acids Research, 1985
- Fibre diffraction of lithium DNA shows structural variability and deviation from a regular helical structure for the B-formFEBS Letters, 1984
- THE CHEMISTRY AND BIOLOGY OF LEFT-HANDED Z-DNAAnnual Review of Biochemistry, 1984
- A thermally driven interconversion of B and Z-DNABiochemical and Biophysical Research Communications, 1983
- Wrinkled DNANucleic Acids Research, 1983
- TAUTOMERIC FORMS IN A POLYNUCLEOTIDE HELIX AND THEIR BEARING ON THE STRUCTURE OF DNAProceedings of the National Academy of Sciences, 1961
- Some Factors in the Interpretation of Protein DenaturationAdvances in Protein Chemistry, 1959