X-ray diffraction studies of DNA at reduced water contents

Autor: BRAM, STANLEY, BAUDY, PIERRE
Zdroj: Nature; August 1974, Vol. 250 Issue: 5465 p414-416, 3p
Abstrakt: REDUCED water contents probably stimulate most closely the local environment about DNA when it is complexed with protein. At low water contents, less than about six water molecules per nucleotide, the equilibrium conformation for pure DNA is the A form1,2. The A form does not alter with base composition3whereas the B states of DNA are strongly correlated with chemical composition4. The A conformation (A state) is the only one which can be called a distinct form. There are many B type conformations all having ten base pairs per turn. ‘C form’ is a misnomer. We use the term ‘C state’ or type for structures having a pitch between 29 and 33A and a diffraction intensity distribution of weak, strong, then weak on the first three layer lines.
Databáze: Supplemental Index