Francis Crick

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Francis Harry Compton Crick (June 8, 1916 – July 28, 2004) was an English physicist, molecular biologist, and neuroscientist. He received, together with James Dewey Watson, Rosalind Franklin and Maurice Wilkins, the Nobel Prize in Medicine in 1962 "for their discoveries concerning the molecular structure of deoxyribonucleic acids (DNA) and their importance for the transfer of information in matter. viva". Watson and Crick's discovery is based on a theory developed by Franklin, however by the time Watson, Crick and Wilkins received the Nobel Prize, Franklin had already passed away, which prevented him from being awarded the Nobel (at that time it was not awarded). the post-mortem award).

Crick also received the Royal and Copley medals of the Royal Society of London (1972 and 1975), as well as the Order of Merit (November 27, 1991).

Biography

Francis, the eldest son of Harry Crick and Anne Elizabeth Wilkins, was born and raised in Weston Favell, a small town near Northampton where his father and uncle worked in a shoe factory. Since childhood he had an interest in science and learned everything he could from books. As a child his parents took him to the Congregationalist church and at the age of 12 he told his mother that he no longer wanted to attend. He preferred scientific research to the beliefs of any dogma. He attended Northampton Grammar School (now Northampton School for Boys) and after the age of 14 received a scholarship to study Mathematics, Physics and Chemistry at London's Mill Hill School. He studied Physics at University College London, after being rejected by Cambridge University, and graduated with a Bachelor of Science in 1937 at the age of 21. Contemporaries of his in research on DNA, or deoxyribonucleic acid Rosalind Franklin and Maurice Wilkins attended Cambridge University, in Newnham and St. Johns, respectively.[citation needed]

Glass work commemorating Francis Crick
The chemical structure of DNA unveiled by Crick, Watson and Franklin
DNA model by Francis Crick, Watson and Franklin

Thus, for his doctorate he worked on a project to measure the viscosity of water at high temperatures, which he later described as boring, in the laboratory of physicist Edward Neville da Costa Andrade, but with the start of World War II, an incident in which a bomb fell on the roof of the laboratory, destroying his experimental apparatus, cut short his career as a physicist.

Shortly before World War II, he joined research on magnetic and acoustic underwater mines in 1939 on behalf of the British Royal Navy. He worked on the design of a new mine, which was effective against German minesweepers. After the war, he became interested in biology and chemistry.

After the war, in 1947, Crick began studying biology and was part of a major migration of scientists from physics to biological research. This migration was possible due to the influence of physicists like John Randall, who helped win the war with inventions like radar. Crick had to move from the "elegance and profound simplicity" of physics to the "elaborate chemical mechanisms in which natural selection has evolved over billions of years." He described this transition "almost as if one had been born again." According to Crick, the experience of learning physics taught him important things, and the conviction that since physics was already a success, great advances could also be made in other sciences such as biology. Crick felt that this attitude encouraged him to be more daring than typical biologists, who tended to worry about problems in biology, paying no attention to achievements in physics.

For almost two years, Crick worked studying the physical properties of the cytoplasm at the Cambridge Strangeways Laboratory, headed by Honor Bridget Fell, until he joined Max Perutz and John Kendrew at the Cavendish Laboratory in Cambridge. This laboratory was under the general direction of Lawrence Bragg, a Nobel Prize winner in 1915 at the age of 25. Bragg was an important influence in the effort to beat the American chemist, Linus Pauling, in discovering the structure of DNA, after he had determined the alpha-helix structure of proteins. At the same time, he was also in competition with John Randall's lab, who turned Crick out of his lab. In 1951 he began to work with James Watson and devoted all his time to the structure of the DNA molecule, already identified by biologists as the key to beginning to understand genetics.

Based on X-ray crystallographic analyzes by Rosalind Franklin, on Crick's specific skills in genetics and biological processes, and on Watson's crystallography, they propose the double helix structure of the DNA molecule, published on April 25, 1953 in the journal Nature.

The structure of the double helix molecule that is DNA gave the world the key to understand all the secrets of life: all life on earth exists solely thanks to this ubiquitous DNA, from the smallest bacterium to the man. This discovery earned him the Nobel Prize in Medicine in 1962 together with James Dewey Watson and the British of New Zealand origin Maurice Wilkins, whose works served as the basis. Despite the important contribution of the physicist Rosalind Franklin, she did not obtain this recognition, since she had died in 1958 and the Nobel is not awarded posthumously.

While numerous teams of scientists made efforts, wasted for lack of powerful enough microscopes, to try to read the structure of the molecule, Crick and Watson discovered that by crystallizing the molecule and subjecting it to beams of X-rays, of which If the different modes of diffraction were then studied, it was possible to discern clues about the double helix structure of DNA. The structure was not determined in a classical way, like other structures determined by X-ray crystallography, rather, it was proposed as the model that best fit the X-ray diffraction images obtained by Rosalind Franklin, without being in any way a "structure" with determined resolution.

Each part of the molecule has four chemical bases facing two by two: adenine with thymine, and cytosine with guanine. These four chemical bases, abbreviated as A, T, C, and G, make up the alphabet by which genes are written along the DNA strands. They also explain that each piece of DNA is a double mirror of the one in front of it, which explains why DNA can copy and reproduce. Crick and Watson begin to study DNA encryption, which will end in 1966.

Through these studies, they arrived at the formulation of a model that reconstructed the physical and chemical properties of DNA, made up of four organic bases that combined in pairs in a defined manner to form a double helix, which determined a structure helical.

He was awarded the Royal Medal in 1972.

In 1973, he joined the Salk Institute for Biological Studies at the University of San Diego to conduct research in neuroscience. He dedicated his efforts to understanding the brain, and provided the scientific community with numerous ideas and hypotheses about consciousness, and the experimental demonstration of the transmission of still images at 50 Hz through the retina to the brain, which was a fundamental contribution to the future of theories of visual perception.

In 1976, he accepted a teaching position at the University of San Diego, and settled in La Jolla facing the Pacific Ocean.

In 1995, he left his position as President of the Salk Institute for Biological Studies for health reasons.

He died on July 28, 2004 at the University Hospital of San Diego, at age 88, of colon cancer.

Work

Crick established the so-called "central dogma" of biology:

The Central Dogma. This states that once ‘information’ has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of sequence, either of bases in the nucleic acid or of amino acid residues in the protein
Crick, 1958, p. 153
The Central Dogma. This raises that once the "information" has passed to the protein it cannot come out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein is possible, but the transfer of protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of the sequence, or of bases in nucleic acid or of amino acid residues in the protein.
Crick, 1958, p. 153

Directed panspermia

During the 1960s, Crick was concerned with the origins of the genetic code. In 1966, Crick filled in for Leslie Orgel at a meeting where Orgel was to speak on the origin of life. Crick speculated about the possible stages by which an initially simple code with a few types of amino acids might have evolved into the more complex code used by extant organisms. At the time, proteins were thought to be the only type of enzyme, and ribozymes had not yet been identified. Many molecular biologists were puzzled by the problem of the origin of a protein replication system as complex as the one that exists in organisms that currently inhabit the Earth. In the early 1970s, Crick and Orgel further speculated that the production of living systems from molecules was a very rare event in the universe, but that once developed it could be propagated by intelligent life forms that used the technology of space travel, a process they called "directed panspermia." In a retrospective paper, Crick and Orgel noted that they had been overly pessimistic about the possibilities of abiogenesis on Earth when they had assumed that some kind of self-replicating protein system was the molecular origin of life.

In 1976, Crick discussed the origin of protein synthesis in a paper with Sydney Brenner, Aaron Klug, and George Pieczenik. In this work, they speculate that code constraints on nucleotide sequences allow protein synthesis without the need for a ribosome. However, a five base junction is required between the mRNA and tRNA with an anticodon flip creating triplet coding, albeit a five base physical interaction. Thomas H. Jukes pointed out that the coding constraints on the mRNA sequence required for this translation mechanism are still retained.

Books written by Crick

  • Of Molecules and Men (Prometheus Books, 2004; original 1967 edition) ISBN 1-59102-185-5
  • Life Itself (Simon & Schuster, 1981) ISBN 0-671-25562-2
  • What Mad Pursuit: A Personal View of Scientific Discovery (reprint, 1990) ISBN 0-465-09138-5. Spanish edition: What a crazy purpose. (1989) 1st. ed. Metatemas; 19: Tusquets, Barcelona. ISBN 84-7223-137-2
  • The Astonishing Hypothesis: The Scientific Search For The Soul (reprint, 1995) ISBN 0-684-80158-2. Spanish edition: Scientific search of the soul: a revolutionary hypothesis for the 21st century. (1994) Debate, Madrid. ISBN 84-7444-824-7
In a comment on this book, published in Science magazine in February 1994, John J. Hopfield concluded the following: "...an eloquent attempt to place consciousness, the essence of our humanity, in the realm of science, which should be read by every scientist who is precious."

Books about Crick

  • James Dewey Watson, The Double Helix: A Personal Account of the Discovery of the Structure of DNA, Atheneum, 1980, ISBN 0-689-70602-2. Double propeller. Plaza and Janés, Esplugas de Llobregat, Barcelona. A recent and affordable edition: Double helix: personal account of DNA discovery. 2000, Pocket Book (Alianza Editorial). Science and Technology; 2752 Biology. Editorial Alliance, Madrid. ISBN 84-206-3570-7
Published for the first time in 1968, this book is a good approach to Crick and Watson's research and served as the basis of the award-winning television documentary Life StoryBBC Horizon.
  • Francis Crick and James Watson: Pioneers in DNA Research by John Bankston, Francis Crick and James Dewey Watson (Mitchell Lane Publishers, Inc., 2002) ISBN 1-58415-122-6

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