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Watson - Crick - Double Helix structure of the DNA
As we got this task to talk about an inventor I had immediately the idea of talking about one of the most important discoveries in the world and this is the deoxyribonucleic acid - in short DNA. With the discovery of the molecular structure of the DNA it was also explained how the genetic material can be copied and this made this discovery so special.
The two men, who found the Double Helix structure, were James Dewey Watson and Francis Harry Compton Crick.
James Dewey Watson was born on the 6th April 1928 in Chicago where he spent his whole childhood and attended the Horace Man Grammar School and later the South Shore High School. He was a child prodigy as he started studying with 15 at the University of Chicago. He completed his study of Zoology in 1947 and got a grant on the Indiana- University in Bloomington. Inspired by the book "What is life" by Erwin Schrödinger Watson decided to research genes and therefore it's no surprise he did his doctorate with a genetic examination about virus in 1950. After this graduation he went to Copenhagen where he met Maurice (Hugh Frederick) Wilkins who had started to research and analyse the DNA- molecules with X- Rays. For this reason Watson's interest in the structure of the DNA was aroused.
In 1952 he went on the "Cavendish Laboratory" on the University of Cambridge where he worked together with Francis Harry Compton Crick. Together they found out the molecular structure of the DNA but about this I want to talk later in more detail.
In 1955 he went to Harvard and in 1962 he got the Nobel prize for medicine together with Crick and Wilkins. In 1968 he became director of the "Cold Spring Harbor Laboratory" in New York, which developed to a leading research institute in molecular biology. In the same year he published his book: "The double Helix" where he describes the discovery of the DNA- structure in a humorous way. From 1988 to 1992 he was the head of the Human Genome Project but after that he moved out of public.
Although he only published some results of research, he is one of the hundred most influential personalities, but also a controversial scientist as he supports the killing of genetic handicapped foetus.
His partner by the discovery was Francis Harry Compton Crick who was born 8th June 1916 in Northampton in Great Britain. Already in school he was interested in natural science and therefore he studied physics at the University College in London. From 1940 to 1947 he was married with Ruth Doree Dodd and they have together the son Michael. After he had read "What is life? The physical aspects of Living Cell" by Erwin Schrödinger he wanted to connect physics with biology and so he started to study biology in 1947. In 1949 he went on the "Cavendish Laboratory" and got in contact to Watson. One funny thing about him is that he baptized his house "GOLDEN HELIX". Later he worked at the "Salk Institute" in California especially in the field of neurobiology. He died last year on the 26th April in San Diego.
Now you know about the two research scientists but how did they found out the Double Helix structure?
At first one thing is really important. As they met 1951 at the "Cavendish Laboratory" they were different age groups, Crick was 35 and Watson 12 years younger but their connection was ambition, thoughtlessness and their fascination for the human genotype.
Actually they had to work on different tasks but they spent most of their time together and tried to find out how the DNA is structured. The components were already known but no one knew how they were connected and how they were worked together.
From 1951 to 1953 they built mock- ups out of cardboard for their hypothetical DNA- structure but they hadn't the right idea. Not until 1953 when Watson got the right idea with the help of X- Ray from the DNA from Maurice Wilkins and his assistant Rosalind Franklin who never was honoured for her help. Then in 1953 they published their discovery in the magazine "NATURE".
They had found out that the structure is similar to a screwed rope ladder and therefore they named it Double Helix.
As you already know out of biology lessons in class 11 the DNA consists of one sugar particle, which is desoxyribose, one phosphate particle and one organic base, which are together one unit. In addition to that they said that Guanine and Cytosine constitute one base couplet and Adenine and Thymine another one. Furthermore Guanine and Adenine belong to purines and Cytosine and Thymine belong to pyrimidines. They also found the connections: The hydrogen bridges. Between Guanine and Cytosine are three and between Adenine and Thymine are two bridges.
Besides this their discovery implicates a copy of genetic material, which they also mentioned in their article. 1962 they got the Nobel Prize for the "Discovery of the molecular structure of nucleic acids and their importance for information- transmission in inner living substance". This was the coronation of their work which brought much light into biological problems.
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