Background
Jean Weigle was born in Geneva, Switzerland, where he obtained his Doctor of Philosophy in physics in 1923, from the University of Geneva.
Jean Weigle was born in Geneva, Switzerland, where he obtained his Doctor of Philosophy in physics in 1923, from the University of Geneva.
University of Geneva.
He is known for his major contributions on field of bacteriophage λ research, focused on the interactions between those viruses and their East. coli hosts. He died in Pasadena, California, after suffering a heart attack in 1968. As a physicist he was awarded for his research on of x-ray diffraction to the study of crystal structure.
The effects of temperature on this diffraction.
The diffraction of light by ultrasonics. He was working as professor of Physics at the University of Pittsburgh in the 1920s.
At the University of Geneva he became director of the Institute of Physics in 1931. He developed the first electron microscope made in Switzerland, an important factor for the studies of molecular biology leading to creation in 1964 of the Institute of Molecular Biology (MOLBIO) by Edouard Kellenberger and others
After suffering his first heart attack in 1946 he emigrated to the United States of America in 1948, resigned from the faculty of the University of Geneva and went to CalTech in Pasadena, California.
There he turned to biology and worked in the Phage group of Max Delbrück, Seymour Benzer, Elie Wollman, and Gunther Stent. He helped in their research the Nobel laureate Werner Arber, George Streisinger, and Giuseppe Bertani also known as "Joe" or "Gio". In 1952, Salvador Luria had discovered the phenomenon of "restriction modification" (the modification of phage growing within an infected bacterium, so that upon their release and re-infection of a related bacterium the phage’s growth is restricted), (also described in Luria’s autobiography, pgs 45 and 99).
Work by Jean Weigle and Giuseppe Bertani at almost the same time, and later work by others clarified the basis for this phenomenon.
They showed that restriction was actually due to attack by specific bacterial enzymes on the modified phage’s deoxyribonucleic acid. This work led to the discovery of the class of enzymes now known as "restriction enzymes." These enzymes allowed controlled manipulation of deoxyribonucleic acid in the laboratory, thus providing the foundation for the development of genetic engineering. He is most noted for his demonstration, with Matthew Meselson, of Caltech and Grete Kellenberger of Geneva, that genetic recombination involves actual breakage and reunion of deoxyribonucleic acid molecules.
He created the classic induction of a lysogen, which involved irradiating the infected cells with ultraviolet light. He demonstrated through his classical experiments the inducible nature of the deoxyribonucleic acid repair system.
The induction of deoxyribonucleic acid damage-response genes in bacteria has come to be known as the SOS response.
This response includes deoxyribonucleic acid damage inducible mutagenesis (now referred to as Weigle mutagenesis in his honor) and inducible deoxyribonucleic acid repair following deoxyribonucleic acid damage (termed Weigle reactivation). "So Weigle was the pioneer of the whole lambda genetics business, which is now a real industrial operation". "The interest of physical scientists such Max Delbrück and Jean Weigle in the 20th Century had a revolutionizing effect on biology".
The Weigle lecture honors his memory, since he was instrumental for the development of Molecular Biology in Geneva.