{{Short description|Swiss biologist (1901–1968)}} {{Infobox scientist | birth_name = Jean-Jacques Weigle | birth_date ={{birth date |1901|7|9|df=yes}} | birth_place = Geneva, Switzerland | death_date = {{death date and age |1968|12|28 |1901|7|9|df=yes}} | death_place = Pasadena, California | other_names = | fields = Physics, biology | workplaces = University of Pittsburgh, University of Geneva, Caltech | education = University of Geneva (Ph.D.) | known_for = Contributions to bacteriophage λ research | awards = | spouse = Ruth Juliette Falk | partner = <!--(or | partners = )--> }} '''Jean-Jacques Weigle''' (9 July 1901 – 28 December 1968) was a Swiss molecular biologist at Caltech and formerly a physicist at the University of Geneva from 1931 to 1948. He is known for his major contributions on field of bacteriophage λ research, focused on the interactions between those viruses and their ''E. coli'' hosts.<ref name=Delbruck>{{cite web|last=Max Delbrück|author-link=Max Delbrück|first=& Robert Edgar|title=Jean-Jacques Weigle, a tribute|url=http://calteches.library.caltech.edu/279/1/jean.pdf|publisher=Caltech|access-date=5 October 2011}}</ref>
==Biography== Jean Weigle was born in Geneva, Switzerland,<ref>{{cite book|last=Hershey|first=Alfred Day|title=The Bacteriophage Lambda|url=https://archive.org/details/bacteriophagelam00hers|url-access=registration|year=1971|publisher=Cold Spring Harbor}}</ref> where he obtained his PhD in physics in 1923, from the University of Geneva. He married Ruth Juliette Falk, a widow.<ref>{{cite news|title=Teacher weds wealthy widow|url=https://news.google.com/newspapers?nid=1129&dat=19310910&id=iZUxAAAAIBAJ&sjid=RmkDAAAAIBAJ&pg=3898,1304613|access-date=5 October 2011|newspaper=Pittsburgh Post-Gazette|date=10 September 1931}}</ref> He died in Pasadena, California, after suffering a heart attack in 1968.<ref name=Delbruck />
==Research== As a physicist he was noted for his research on 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) in Geneva by Eduard Kellenberger and others.
After suffering his first heart attack in 1946 he emigrated to the US 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. While at Caltech, Weigle worked with other notable molecular biologists, including George Streisinger (whom Weigle mentored as a postdoctoral researcher<ref>{{cite web |last1=Stahl |first1=Frank |title=George Streisinger: 1927 - 1984: a biographical memoir |url=http://www.nasonline.org/publications/biographical-memoirs/memoir-pdfs/streisinger-george.pdf |website=National Academy of Sciences USA |access-date=29 March 2019}}</ref>), Giuseppe Bertani, and Nobel laureate Werner Arber.<ref>{{cite web |last1=Arber |first1=Werner |title=Biographical Sketch |url=https://www.nobelprize.org/prizes/medicine/1978/arber/biographical/ |website=nobelprize.org}}</ref>
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),<ref>{{cite journal | pmid = 12999684 | volume=64 | title=A nonhereditary, host-induced variation of bacterial viruses | pmc=169391 | date=October 1952 | journal=J. Bacteriol. | pages=557–69 | last1 = Luria | first1 = SE | last2 = Human | first2 = ML | issue=4 | doi=10.1128/jb.64.4.557-569.1952 }}</ref> (also described in Luria's autobiography,<ref>Salvador E. Luria. A Slot Machine, A Broken Test Tube: An Autobiography. Harper & Row, New York: 1984. Pp. 228. {{ISBN|0-06-015260-5}} (USA and Canada)</ref> pgs. 45 and 99). Work by Jean Weigle and Giuseppe Bertani at almost the same time,<ref>{{cite journal | pmid = 13034700 | volume=65 | title=Host controlled variation in bacterial viruses | pmc=169650 | date=February 1953 | journal=J. Bacteriol. | pages=113–21 | last1 = Bertani | first1 = G | last2 = Weigle | first2 = JJ | issue=2 | doi=10.1128/jb.65.2.113-121.1953 }}</ref> 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 DNA. This work led to the discovery of the class of enzymes now known as "restriction enzymes." These enzymes allowed controlled manipulation of DNA 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 DNA 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 DNA repair system.<ref name=Shapiro />
The induction of DNA damage-response genes in bacteria has come to be known as the SOS response. This response includes DNA damage inducible mutagenesis<ref name=Weigle>{{cite journal | pmid = 16589315 | volume=39 | title=Induction of Mutations in a Bacterial Virus | pmc=1063835 | year=1953 | journal=Proc Natl Acad Sci U S A | pages=628–36 | last1 = Weigle | first1 = JJ | issue=7 | doi=10.1073/pnas.39.7.628 | bibcode=1953PNAS...39..628W | doi-access=free }}</ref> (now referred to as Weigle mutagenesis in his honor) and inducible DNA repair following DNA damage<ref name=Weigle /> (termed Weigle reactivation).<ref name=Shapiro>{{cite book|last=Shapiro|first=James A.|author-link=James A. Shapiro|title=Evolution: A View from the 21st Century|year=2011|publisher=FT Press Science|isbn=978-0-13-278093-3}}</ref>
==Selected works== *{{cite journal | last1 = Weigle | first1 = J. J. | last2 = Delbrück | first2 = M. | year = 1951 | title = Mutual exclusion between an infecting phage and a carried phage | journal = J. Bacteriol. | volume = 62 | issue = 3| pages = 301–318 | doi = 10.1128/jb.62.3.301-318.1951 | pmid = 14888647 | pmc = 386128 }} *{{cite journal | last1 = Weigle | first1 = J. J. | year = 1953 | title = Induction of Mutations in a Bacterial Virus | journal = Proc Natl Acad Sci USA | volume = 39 | issue = 7| pages = 628–636 | doi = 10.1073/pnas.39.7.628 | doi-access = free | pmc = 1063835 | pmid = 16589315 | bibcode = 1953PNAS...39..628W }}
==Awards and honours== In 1947 he received an honorary doctorate from Case Institute of Technology. In 1962 he was awarded the ''Prix des trois physiciens''.<ref>{{cite web|url=https://hls-dhs-dss.ch/fr/articles/048015/2015-01-11/|author=Joye-Cagnard, Frédéric|title=Jean Weigle|website=Dictionnaire Historique de la Suisse (DHS)}} 11 Janvier 2015</ref>
==Legacy== "So Weigle was the pioneer of the whole lambda genetics business, which is now a real industrial operation".<ref name=Benzer>{{cite web|last=Benzer|first=Seymour|title=Benzer, Seymour. Interview by Heidi Aspaturian. Pasadena, California, September 11–February 1991.|url=http://oralhistories.library.caltech.edu/27/01/OH_Benzer_S.pdf|publisher=Oral History Project, California Institute of Technology Archives|access-date=7 October 2011}}</ref> "The interest of physical scientists such Max Delbrück and Jean Weigle in the 20th Century had a revolutionizing effect on biology".<ref name=Shapiro /> In his honor the institutions where he worked created the Weigle Memorial Service and the Weigle Memorial Lecture at Caltech, and several friends established the Jean Weigle Memorial Fund. The Weigle lecture honors his memory, since he was instrumental for the development of Molecular Biology in Geneva.
==References== {{Reflist}}
==External links== *[http://www.molbio.unige.ch/eng/weigle_lectures Weigle lectures] {{Webarchive|url=https://web.archive.org/web/20120425050430/http://www.molbio.unige.ch/eng/weigle_lectures |date=2012-04-25 }} *[http://www.molbio.unige.ch/eng/about/history History of MOLBIO at Geneva University]{{Dead link|date=December 2025 |bot=InternetArchiveBot }} {{Authority control}}
{{DEFAULTSORT:Weigle, Jean}} Category:1901 births Category:1968 deaths Category:Molecular biologists Category:Mutagenesis Category:Swiss physicists Category:University of Geneva alumni Category:Academic staff of the University of Geneva Category:Scientists from Geneva Category:California Institute of Technology faculty Category:Phage workers Category:20th-century Swiss biologists Category:University of Pittsburgh faculty