Discovering the structure of DNA BBC Bitesize

Photo 51 is an X-ray based fiber diffraction image of a paracrystalline gel composed of DNA fiber [1] taken by Raymond Gosling, [2] [3] a graduate student working under the supervision of Rosalind Franklin in May 1952 at King's College London, while working in Sir John Randall 's group. Rosalind Franklin used X-ray diffraction to determine the structure of DNA molecules. One of her best X-ray pictures is numbered Photo 51 and is shown in Fig. 1 (a). This photo was instrumental to J. D. Watson and F. Crick in deducing the double-helix model of DNA.

The Structure of DNA by Ron Vale

The pattern of the X-rays bouncing off atoms (a phenomenon called "diffraction") gave information about their location in the molecule. One of the pioneers of this technique, called "X-ray crystallography," was Linus Pauling, who worked at the California Institute of Technology in Pasadena. A nucleotide is made up of a sugar (deoxyribose), a phosphate group, and one of four nitrogenous bases: adenine (A), thymine (T), guanine (G) or cytosine (C). C and T bases, which have just one ring, are called pyrimidines, while A and G bases, which have two rings, are called purines. X-ray diffraction monocristal tridimensional structure Author Information Show + 1. Introduction In 1953, James Watson and Francis Crick revealed the double helical structure of DNA using the results of Rosalyn Franklin obtained by X-ray scattering on natural filaments formed by DNA molecules [ 1 ]. 1943: X-ray Diffraction of DNA William Astbury, a British scientist, obtained the first X-ray diffraction pattern of DNA. X-ray diffraction patterns of crystallized molecules can reveal their structures with atomic precision. Astbury obtained X-ray diffraction patterns of uncrystallized DNA.

A' form DNA. An example of an Xray diffraction pattern obtained by

Scientists began collecting X-ray diffraction patterns of DNA in the 1930s before they confirmed that DNA contained genes. William Thomas Astbury, a crystallographer working at the University of Leeds in Leeds, England, gathered the first diffraction patterns of DNA in 1937. This is the iconic X-ray diffraction photograph of DNA taken by physical chemist Rosalind Elsie Franklin and PhD student Raymond G. Gosling. The genetic material glimpsed in Photo 51 connects all living things and the image thus metaphorically captures human past, present, and future. It also marks an important milestone in science. Introduction In this Post we describe our attempt to replicate the experiment on X-ray diffraction by the DNA molecule. This experimental research, conducted at the time by Rosalind Franklin, allowed us to understand the structure of the DNA molecule. Franklin and Gosling's X-ray diffraction image of B DNA, known as Photograph 51.. (X-ray diffraction experiments in the 1930s had inadvertently used a mixture of the A and B forms of DNA.

Discovering the structure of DNA BBC Bitesize

The discovery of the structure of DNA in 1953 was made possible by Dr Rosalind Franklin's X-ray diffraction work at King's. Her creation of the famous Photo 51 demonstrated the double-helix structure of deoxyribonucleic acid: the molecule containing the genetic instructions for the development of all living organisms. Crick himself had co-authored a paper on the theory of diffraction of X-rays by helices 5. In late 1951, he and Watson combined that theory with what they knew about the chemistry of DNA, and what. Rosalind Franklin Rosalind Elsie Franklin (25 July 1920 - 16 April 1958) [1] was a British chemist and X-ray crystallographer whose work was central to the understanding of the molecular structures of DNA (deoxyribonucleic acid), RNA (ribonucleic acid), viruses, coal, and graphite. [2] 15337. Use of X-ray crstallography to prove that DNA is crystalline, Maurice Wilkins Maurice Wilkins talks about obtaining an X-ray diffraction pattern. ID: 15337 Source: DNAi 16422. Animation 19: The DNA molecule is shaped like a twisted ladder. James Watson and Francis Crick explain how they solved the structure of DNA.

What is XRay Crystallography? (with pictures)

Rosalind Franklin used a technique called X-ray crystallography to find out the 3D shape of molecules. She applied this technique to different samples. Early in her career she worked on carbon and coal. Later she started working on biological subjects. She made major contributions to the discovery of the shape of DNA. This X-ray diffraction picture of a DNA molecule was Watson's inspiration (the pattern was clearly a helix). Using Franklin's photograph and their own data, Watson and Crick created their famous.