History and sicovery DNA

  • Discovery of Nucleic Acids

    Friedrich Miescher, swiss physical and biologist, was the discoverer of Nuclein. He discovered the nuclein from the white blood nuclei.
  • Discovery of DNA Components

    Discovery of DNA Components
    They were discovered by Phoebus Levene, including sugar, phosphate and the base that he called nucleotides.
    But he failed to discover the structure, he thought they were structured in tetrahedra.
    But his work was ultimately a key in the final determination of the structure of DNA.
  • Bacterial Transformation

    Bacterial Transformation
    Frederick Griffith was the first person to demonstrate bacterial transformation, with his experiment with mice and two bacterial strains. And it showed that the bacteria could transfer genetic information during the transformation.
  • Avery, MacLeod and McCarthy

    Avery, MacLeod and McCarthy
    This group of scientists demonstrated that DNA was responsible for the transformation, and they demonstrated it based on Frederick Griffith's experiment.
  • Double helix

    Double helix
    They described DNA as a double helix with sugars and phosphates in the center and nucleobases on the outside. This was incorrect as it made no chemical sense.
  • Rosalin Franklin and Photo 5l

    Rosalin Franklin and Photo 5l
    Rosalind took many photographs about DNA, discovered how to see the shape in cells. The most famous photo was 51 which clearly shows the X of the double helix.
    But before she finished the calculations to be able to publish it, Maurice Wilkins obtained image 51 and built a model from Rosalind's photograph.
  • Chargaff’s rules

    Chargaff’s rules
    The Chargaff's rule is based on the fact that the quantities of adenine are the same as the quantities of thymine and the quantities of cytosine are the same as the quantities of Guanine, in all the spices.
    This was very important for the discovery of the structure of DNA.
  • Hershey & Chase

    Hershey & Chase
    Hershey & Chase discovered that the genetic material was not in the protein but in the DNA. Thanks to his experiment with bacteria.
  • Pauling’s Triple Helix

    Pauling’s Triple Helix
    Linus Pauling discovered the triple helix, which was a model of the structure of DNA, with phosphorus and sugar on the inside and the nucleobases on the outside. But it turned out to be wrong.