Heroes and Cultural Identity Project

SCE Heroes - Francis Crick

Francis Crick

Francis Harry Compton Crick was an English molecular biologist who is most recognised by his work towards the discovery of the structure of the DNA molecule. Crick was interested in how molecules make the adaptation from non-living to living. In 1949 he joined the Max Perutz project at Cambridge University where he used X-ray crystallography to study the structure of large molecules. He knew that a type of macromolecule, such as protein, was likely to be the genetic molecule.

A breakthrough was made in 1951 with the discovery of the Alpha Helix (a molecule in which the amino acids are arranged in a right-handed helical structure). From this Crick was able to further investigate the structure of DNA and in late 1953, he and co-worker James D Watson published a developed model for a helical structure of DNA.

Together after looking into and studying Rosalind Franklin's reports and unpublished X-ray diffraction images they realized that their first model was incorrect and so with the aid of Franklins reports were able to construct a molecular model of DNA in 1952. This new model contained bases on the inside. During the construction of this model it was learned that a the orientation of the two nucleotide chain backbones worked best at an anti-parallel direction to orient the base pairs in the centre of a double helix.

After continuing the study of DNA and moving on to look at RNA, Crick had found proof that the genetic code is a triplet code.

Kathryn Burgess is a science student following a one year university access course in biological sciences.