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00:00The Nobel Prize. The Nobel Prize in Physiology of Medicine 1962 was awarded jointly to Francis
00:21Crick, James Watson and Maurice Wilkins. For their discoveries concerning the molecular
00:27structure of nucleic acids and its significance for information transfer in living material.
00:34During the 1930s a number of laboratories began to use a method called X-ray crystallography to map
00:41large biologically important molecules. Maurice Wilkins and Rosalind Franklin worked to determine
00:49the structure of the DNA molecule in the early 1950s at King's College in London. While they did
00:56not succeed in mapping the structure. Their results, not least of all Franklin's X-ray diffraction images,
01:03were important in Francis Crick's and James Watson's eventual unlocking of the mystery, a long spiral
01:10with twin threads. In 1944 Oswald Avery proved that DNA is the bearer of organisms' genetic code.
01:20Further explanation was provided when James Watson and Francis Crick determined the structure of the
01:25DNA molecule in 1953. The structure, a long double helix, contains a long row of pairs of four
01:33different nitrogen bases, which allow the molecule to function like a code. The molecule's structure
01:40also explains how it is able to copy itself. The nitrogen bases always pair in the same constellations,
01:47so that if a molecule is split, its halves can be supplemented so that they form copies of the
01:53original molecule. Francis Harry Compton Crick was born on June the 8th 1960 at Northampton, England,
02:01being the elder child of Harry Crick and Annie Elizabeth Wilkins. Crick was educated at Northampton
02:08Grammar School and Mill Hill School, London. Supported by a student ship from the Medical Research Council
02:15and with some financial help from his family, Crick went to Cambridge and worked at the Strange
02:20Ways Research Laboratory. In 1949 he joined the Medical Research Council unit, headed by M. F. Perutz,
02:28of which he has been a member ever since. A critical influence in Crick's career was his friendship,
02:36beginning in 1951 with J. D. Watson, then a young man of 23, leading in 1953 to the proposal of the double
02:46helical structure for DNA and the replication scheme. Crick and Watson subsequently suggested a general
02:53theory for the structure of small viruses. Crick, in collaboration with A. Rich, has proposed structures
03:01for polyglycine 2 and collagen and a structure for polyadenylic acid. In recent years, Crick,
03:09in collaboration with S. Brenner, has concentrated more on biochemistry and genetics, leading to ideas
03:17about protein synthesis, the adapter hypothesis, and the genetic code. During the spring of 1951,
03:26Jane Watson went with Calca to the Zoological Station at Naples. There, at a symposium late in May,
03:34he met Maurice Wilkins and saw, for the first time, the X-ray diffraction pattern of crystalline DNA.
03:42This greatly stimulated him to change the direction of his research toward the structural chemistry of
03:49nucleic acids and proteins. Fortunately, this proved possible when Luria, in early August 1951, arranged
03:59with John Kendrew for him to work at the Cavendish laboratory, where he started work in early October 1951.
04:09He soon met Crick and discovered their common interest in solving the DNA structure. They thought it
04:16should be possible to correctly guess its structure given both the experimental evidence at King's College,
04:22plus careful examination of the possible stereochemical configurations of polynucleotide chains.
04:30Their first serious effort in the late fall of 1951 was unsatisfactory. Their second effort,
04:38based upon more experimental evidence and better appreciation of the nucleic acid literature,
04:45resulted early in March 1953, in the proposal of the complementary double helical configuration.
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