In this article we will discuss about the Chargaff-equivalence rule for DNA. By 1948, a chemist Erwin Chargaff started using paper chromatography to analyse the base composition of DNA from a number of studies. In 1950, Chargaff discovered that in the DNA of different types of organisms the total amount of purines is equal to the total amount of pyrimidines [...]
The following components of deoxyribonucleotide (DNA) have been described: 1. A Five Carbon Ring 2. Nitrogenous Base 3. A Phosphate Group. 1. A Five Carbon Ring: Deoxyribose is a pentose sugar consisting of five carbon atoms. The first and fourth carbon atoms of this sugar combine with one oxygen atom and form a ring. The fifth atom (5') forms –CH2 [...]
In this article we will discuss about the X-ray crystallographic studies of DNA. In 1920, the basic chemical composition of nucleic acid was elucidated through the efforts of P.A. Levene. In 1940, for the first time W.T. Astbury gave first three dimensional structure of DNA model studied through X-ray crystallography. He concluded that its flat nucleotides get stacked to form [...]