Francis Harry Compton Crick OM. 8 June 1916 — 28 July 2004

The first half of the twentieth century saw a profound change in our understanding of the chemistry underlying biology. We came to learn in detail how the small molecules upon which life is based are interconverted by specific enzymes, a web which increased in complexity and became modern biochemistry. Intellectually, a quite separate development—molecular biology—arose from physicists and chemists studying the structure of proteins with X-rays, and biologists studying viruses that infect bacteria. Its intellectual thrust was to discover how information in genes is expressed and controlled. This led to a revolution in our understanding of biology, and no person was more influential in shaping and guiding this emerging field than Francis Crick.