Watson-Crick structure of DNA

Figure 5-2 A distorted (flattened) view of the Watson-Crick structure of DNA showing the hydrogen-bonded base pairs.

The first attempt appears to be that of Hayashi and Munakata [20a].These authors start from the well-known Watson-Crick structure of DNA, which is a succession of... 

The normal Watson-Crick structure of DNA is now referred to as the p-form. What are the a and Z forms, and how do they differ from the p-form ... 

C13-0102. hi the 1950s, Edwin Chargaff of Columbia University studied the composition of DNA from a variety of plants and animals. He found that the relative amounts of different bases changed from one species to another. However, in every species studied, the molar ratios of guanine to cytosine and of adenine to thymine were found to be very close to 1.0. Explain Chargaff s observations in terms of the Watson-Crick model of DNA structure. 

Brown and Farthing synthesis of [2.2]paracyclophane 1953 - Watson and Crick structure of DNA... 

List the postulates of the Watson-Crick model of DNA secondary structure. 

Watson s vivid and outspoken account of how he and Crick discovered the structure of DNA (and won themselves a Nobel Prize) - one of the greatest scientific achievements of the century. 

The breakthrough came in 1953 when James D. Watson and Francis H. C. Crick proposed a structure for DNA. The Watson-Crick proposal ranks as one of the most important in all of science and has spurred a revolution in our understanding of genetics. The structure of DNA is detailed in the next section. The boxed essay It Has Not Escaped Our Notice. .. describes how it cane about. 

James Dewey Watson (1928- ) was born in Chicago, Illinois, and enrolled in the University of Chicago at age 15. He received his Ph.D. in 1950 at the Unwersity of Indiana and then worked at Cambridge University in England from 1951 to 1953, where he and Francis Crick deduced the structure of DNA. After more than 20 years as professor at Harvard University, he moved in 1976 to the Laboratory of Quantitative Biology at Cold Spring Harbor, Long Island, New York. He shared the 1962 Nobel Prize in medicine for his work on nucleic acids. 

In 1953, James Watson and Francis Crick made their classic proposal for the secondary structure of DNA. According to the Watson-Crick model, DNA under physiological conditions consists of two polynucleotide strands, running in opposite directions and coiled around each other in a double helix like the handrails on a spiral staircase. The two strands are complementary rather than identical and are held together by hydrogen bonds between specific pairs of... 

The secondary structure of DNA is shown in Figure B. This "double helix" model was first proposed in 1953 by James Watson and Francis Crick, who used the x-ray crystallographic data of Rosalind Franklin and Maurice Wilkins. Beyond that, they were intrigued by the results of analyses that showed that in DNA the ratio of adenine to thymine molecules is almost exactly 1 1, as is the ratio of cytosine to guanine ... 

By now the stage was set for the discoveiy of the three-dimensional structure of DNA, the so-called secondary structure of the molecule. Some of the best minds in science were working on the problem. In 1953, James D. Watson and Francis Crick of Cambridge University announced that they had discovered the structure of DNA. 

The structure of DNA was discovered by (shown left to right) Francis Crick, James Watson, Maurice Wilson, and Rosalind Franklin. 

---