Max Delbrück

Not to be confused with his uncle, Max Delbrück (chemist), an agricultural chemist.

Max Ludwig Henning Delbrück (German: [maks ˈdɛl.bʁʏk] ^ⓘ; September 4, 1906 – March 9, 1981) was a German–American biophysicist who participated in launching the molecular biology research program in the late 1930s. He stimulated physical scientists' interest into biology, especially as to basic research to physically explain genes, mysterious at the time. Formed in 1945 and led by Delbrück along with Salvador Luria and Alfred Hershey, the Phage Group made substantial headway unraveling important aspects of genetics. The three shared the 1969 Nobel Prize in Physiology or Medicine "for their discoveries concerning the replication mechanism and the genetic structure of viruses".^[5] He was the first physicist to predict what is now called Delbrück scattering.^[6][7][8]

Max Delbrück ForMemRS
Born	Max Ludwig Henning Delbrück (1906-09-04)September 4, 1906 Berlin, German Empire
Died	March 9, 1981(1981-03-09) (aged 74) Pasadena, California, United States
Citizenship	United States^[3]
Alma mater	University of Göttingen
Known for	"discoveries concerning the replication mechanism and the genetic structure of viruses" (Nobel Committee)^[4] Delbrück scattering Luria–Delbrück experiment Saffman–Delbrück model
Spouse	Mary Bruce
Children	Four
Parent	Hans Delbrück (father)
Relatives	Emmi Bonhoeffer (sister)
Awards	ForMemRS (1967)^[1] Mendel Medal (1968) Louisa Gross Horwitz Prize (1969) Nobel Prize in Physiology or Medicine (1969) EMBO Membership (1970)^[2]
Scientific career
Fields	Biophysics
Institutions	Kaiser Wilhelm Institute for Chemistry Vanderbilt University Caltech
Doctoral advisor	Lise Meitner
Doctoral students	Lily Jan, Yuh Nung Jan, Ernst Peter Fischer, Charles M. Steinberg

Early and personal life

 

Delbrück in the early 1940s

Delbrück was born in Berlin, German Empire. His mother was granddaughter of Justus von Liebig, an eminent chemist, while his father Hans Delbrück was a history professor at the University of Berlin. In 1937, Delbrück left Nazi Germany for America—first California, then Tennessee—becoming a US citizen in 1945.^[3] In 1941, he married Mary Bruce. They had four children.

Delbrück's brother Justus, a lawyer, as well as his sister Emmi Bonhoeffer were active along with his brothers-in-law Klaus Bonhoeffer and Dietrich Bonhoeffer in resistance to Nazism. Found guilty by the People's Court for roles in the July 20, 1944 plot to assassinate Hitler, Dietrich and Klaus were executed in 1945 by the RSHA. Justus died in Soviet custody that same year. His son, Tobias Delbruck is a professor at the Institute of Neuroinformatics at the University of Zurich and ETH Zurich.^[9] Professor Tobias Delbruck is also one of the pioneers in the domain of event cameras,^[10] now increasingly being deployed in dynamic vision systems.

Education

Delbrück studied astrophysics, shifting towards theoretical physics, at the University of Göttingen. After completing his Ph.D. there in 1930,^[11] he traveled through England, Denmark, and Switzerland. He met Wolfgang Pauli and Niels Bohr, who interested him in biology.

Career and research

 

Delbrück's workplace in Berlin: Kaiser Wilhelm Institute for Chemistry, now the Free University of Berlin.

Delbrück returned to Berlin in 1932 as an assistant to Lise Meitner, who was collaborating with Otto Hahn on irradiation of uranium with neutrons. Delbrück wrote a few papers, including one in 1933 on gamma rays' scattering by a Coulomb field's polarization of a vacuum. Though theoretically tenable, his conclusion was misplaced, whereas Hans Bethe some 20 years later confirmed the phenomenon and named it "Delbrück scattering".^[12]

In 1935, Delbrück published a collaboration with Nikolay Timofeev-Ressovsky and Karl Zimmer the major work, Über die Natur der Genmutation und der Genstruktur. It was considered to be a major advance in understanding the nature of gene mutation and gene structure.^[13] The work was a keystone in the formation of molecular genetics.^[14] It was also an inspirational starting point for Erwin Schrödinger's thinking, a course of lectures in 1943, and the eventual writing of the book What Is Life? The Physical Aspect of the Living Cell.^[15]

In 1937, he attained a fellowship from Rockefeller Foundation—which was launching the molecular biology research program—to research genetics of the fruit fly, Drosophila melanogaster, in California Institute of Technology's biology department,^[16] where Delbrück could blend interests in biochemistry and genetics.^[17] While at Caltech, Delbrück researched bacteria and their viruses (bacteriophages or phages). In 1939, with Emory L. Ellis,^[18][19] he coauthored "The growth of bacteriophage", a paper reporting that the viruses reproduce in one step, not exponentially as do cellular organisms.

 

Drawing of a plaque in Buttrick Hall, Vanderbilt University commemorating the work of Max Delbrück.^[20]

Although Delbrück's Rockefeller Foundation fellowship expired in 1939, the Foundation matched him up with Vanderbilt University in Nashville, Tennessee, where from 1940 to 1947 he taught physics, yet had his laboratory in the biology department.^[21] In 1941, Delbrück met Salvador Luria of Indiana University who began visiting Vanderbilt.^[21] In 1942, Delbrück and Luria published on bacterial resistance to virus infection mediated by random mutation.^[21] Alfred Hershey of Washington University in St. Louis began visiting in 1943.^[21] The Luria–Delbrück experiment, also called the Fluctuation Test, demonstrated that Darwin's theory of natural selection acting on random mutations applies to bacteria as well as to more complex organisms. The 1969 Nobel Prize in Physiology or Medicine was awarded to both scientists in part for this work. To put this work in its historical perspective, Lamarck in 1801 first presented his theory of Inheritance of Acquired Characteristics, which stated that if an organism changes during life in order to adapt to its environment (for example stretches its neck to reach for tall trees), those changes are passed on to its offspring. He also said that evolution happens according to a predetermined plan. Darwin published his theory of evolution in his 1859 book On the Origin of Species with compelling evidence contradicting Lamarck. Darwin said that evolution is not predetermined but that there are inherent variations in all organisms, and that those variations that confer increased fitness are selected by the environment and passed on to the offspring. In the feud between Lamarck and Darwin, Darwin talked of pre-existing changes, but the nature of these changes was not known and had to await the science of genetics by Gregor Mendel's experiments on pea plants published in 1866. Support for Darwin's theory was provided when Thomas Hunt Morgan discovered that a mutated white-eyed fruit fly among red-eyed flies was able to reproduce true white-eyed offspring. The most elegant and convincing support for Darwin's ideas, however, was provided by the Luria-Delbruck experiment,^[22][23][24] which showed that mutations conferring resistance of the bacterium E. coli to T1 bacteriophage (virus) existed in the population prior to exposure to T1 and were not induced by adding T1. In other words, mutations are random events that occur whether or not they prove to be useful, while selection (for T1 resistance upon challenge with T1 in this case) provides the direction in evolution by retaining those mutations that are advantageous, discarding those that are harmful (T1 sensitivity in this case). This experiment dealt a blow to Lamarckian inheritance and set the stage for tremendous advances in genetics and molecular biology, launching a tsunami of research that eventually led to the discovery of DNA as the hereditary material and to cracking the genetic code. Of course, by then Avery, along with McCloud (and earlier, McCarty) was well on the way to showing the genetic capability of DNA.

In 1945, Delbrück, Luria, and Hershey set up a course in bacteriophage genetics at Cold Spring Harbor Laboratory on Long Island, New York.^[21] This Phage Group spurred molecular biology's early development.^[25] Delbrück received the 1969 Nobel Prize in Physiology or Medicine, shared with Luria and Hershey "for their discoveries concerning the replication mechanism and the genetic structure of viruses".^[5][21][26] The committee also noted that "The honour in the first place goes to Delbrück who transformed bacteriophage research from vague empiricism to an exact science. He analyzed and defined the conditions for precise measurement of the biological effects. Together with Luria he elaborated the quantitative methods and established the statistical criteria for evaluation which made the subsequent penetrating studies possible. Delbrück's and Luria's forte is perhaps mainly theoretical analysis, whereas Hershey above all is an eminently skillful experimenter. The three of them supplement each other well also in these respects." That year, Delbrück and Luria were also awarded by Columbia University the Louisa Gross Horwitz Prize. In late 1947, as Vanderbilt lacked the resources to keep him, Delbrück had returned to Caltech as a professor of biology, and remained there for the rest of his career.^[21] Meanwhile, he set up University of Cologne's institute for molecular genetics.

Awards and honours

In addition to the Nobel Prize, Delbrück was elected a Foreign Member of the Royal Society (ForMemRS) in 1967.^[1] He was elected an EMBO Member in 1970.^[2] The Max Delbruck Prize, formerly known as the biological physics prize, is awarded by the American Physical Society and named in his honour. The Max Delbrück Center, in Berlin, Germany, national research center for molecular medicine of the Helmholtz Association also bears his name.

Later life and legacy

Delbrück helped spur physical scientists' interest in biology. His inferences on genes' susceptibility to mutation was relied on by physicist Erwin Schrödinger in his 1944 book What Is Life?,^[27] which conjectured genes were an "aperiodic crystal" storing codescript and influenced crystallographer Rosalind Franklin and biologists Francis Crick and James D. Watson in their 1953 identification of cellular DNA's molecular structure as a double helix.^[28][29] In 1977, he retired from Caltech, remaining a Professor of Biology emeritus. He became interested in the behavioral sciences and spent some unfruitful effort on mold behavior in the 1960s.

Max Delbrück died, at age 74, on the evening of Monday, March 9, 1981, at Huntington Memorial Hospital in Pasadena, California. On August 26 to 27, 2006—the year Delbrück would have turned 100—family and friends gathered at Cold Spring Harbor Laboratory to reminisce on his life and work.^[30] Although Delbrück held some anti-reductionist views; he conjectured that ultimately a paradox—akin perhaps to the waveparticle duality of physics—would be revealed about life. His view however, was later refuted upon the discovery of the double helix structure of DNA.^[31]

References

1. William Hayes (1982). "Max Ludwig Henning Delbruck. 4 September 1906-10 March 1981". Biographical Memoirs of Fellows of the Royal Society. 28. London: Royal Society: 58–90. doi:10.1098/rsbm.1982.0003. JSTOR 769892.
2. "Max Delbrück EMBO profile". people.embo.org. Heidelberg: European Molecular Biology Organization.^{[permanent dead link]}
3. "Max Delbrück". Encyclopædia Britannica. Encyclopædia Britannica, Inc. from the original on December 26, 2018. Retrieved June 25, 2013. A refugee from Nazi Germany, Delbrück went to the United States in 1937, serving as a faculty member of the California Institute of Technology (1937–39; 1947–81) and of Vanderbilt University (1940–47). He became a U.S. citizen in 1945.
4. . Nobel Foundation. Archived from the original on May 26, 2013. Retrieved June 25, 2013.
5. "The Nobel Prize in Physiology or Medicine 1969" June 27, 2018, at the Wayback Machine, Nobel Media AB 2013, Nobelprize.org, Web access November 6, 2013.
6. Ton van Helvoort (1992). "The controversy between John H. Northrop and Max Delbrück on the formation of bacteriophage: Bacterial synthesis or autonomous multiplication?". Annals of Science. 49 (6): 545–575. doi:10.1080/00033799200200451. PMID 11616207.
7. Lily E. Kay (1985). "Conceptual models and analytical tools: The biology of physicist Max Delbrück". Journal of the History of Biology. 18 (2): 207–246. doi:10.1007/BF00120110. PMID 11611706. S2CID 13630670.
8. Daniel J. McKaughan (2005). "The Influence of Niels Bohr on Max Delbrück". Isis. 96 (4): 507–529. doi:10.1086/498591. PMID 16536153. S2CID 12282400.
9. "https://www.ini.uzh.ch/~tobi/ January 10, 2023, at the Wayback Machine"
10. "https://ieeexplore.ieee.org/document/8050295 October 17, 2022, at the Wayback Machine"
11. "Max Delbrück January 27, 2019, at the Wayback Machine". Encyclopaedia Britannica. britannica.com. Retrieved January 27, 2019.
12. W. Hayes (1992). "Max Ludwig Henning Delbrück – September 4, 1906 – March 10, 1981". Biographical Memoirs of the National Academy of Sciences. 62: 67–117. PMID 11639973. from the original on October 15, 2012. Retrieved July 22, 2012.
13. Timofeeff-Ressovky, N. W., K. G. Zimmer, and M. Delbrück "Über die Natur der Genmutation und der Genstruktur" (Weidmannsche Buchhandlung, 1935). Nachrichten Göttingen March 3, 2022, at the Wayback Machine - "Über die Natur der Genmutation und der Genstruktur" (1935).
14. Strauss BS. A Physicist's Quest in Biology: Max Delbrück and "Complementarity". Genetics. 2017 Jun;206(2):641-650. doi:10.1534/genetics.117.201517. PMID 28592501; PMC 5499177
15. Erwin Schrödinger What Is Life? The Physical Aspect of the Living Cell (Cambridge University Press, 1944).
16. "MDC celebrates centennial of Max Delbrück". Max Delbrück Center for Molecular Medicine Berli-Buch. September 4, 2006.
17. Stefanie Tapke. "Max Delbrück – Biographical". Biographical article. Nobel Media. from the original on June 12, 2018. Retrieved September 13, 2013.
18. Ellis E. L., Delbrück M. The growth of bacteriophage. J Gen Physiol. 1939 Jan 20;22(3):365-84. PMID 19873108
19. Ellis E.L. "Bacteriophage: One-step growth curve" in Phage and the Origins of Molecular Biology (2007) Edited by John Cairns, Gunther S. Stent, and James D. Watson, Cold Spring Harbor Laboratory of Quantitative Biology, Cold Spring Harbor, Long Island, New York ISBN 978-0-87969-800-3
20. Max Delbrück and the Next 100 Years of Biology: The Max Delbrück Vanderbilt Centenary Celebration, The Inaugural Vanderbilt Discovery Lecture November 19, 2012, at the Wayback Machine, Held September 14, 2006
21. "Max Delbrück at Vanderbilt, 1940–1947" October 11, 2012, at the Wayback Machine, Vanderbilt University, Web access November 6, 2013.
22. Luria SE, Delbrück M. Mutations of bacteria from virus sensitivity to virus resistance. Genetics. 1943 Nov;28(6):491-511. doi:10.1093/genetics/28.6.491. PMID 17247100; PMC 1209226
23. Luria SE "Mutations of bacteria and bacteriophage" in Phage and the Origins of Molecular Biology (2007) Edited by John Cairns, Gunther S. Stent, and James D. Watson, Cold Spring Harbor Laboratory of Quantitative Biology, Cold Spring Harbor, Long Island, New York, pgs. 173-179. ISBN 978-0-87969-800-3
24. Luria SE. A Slot Machine, a Broken Test Tube. An Autobiography. Harper and Row, New York, 1984. Alfred P. Sloan Foundation Series
25. J.D. Watson (2012). "James D Watson: Chancellor emeritus" December 11, 2013, at the Wayback Machine, Cold Spring Harbor Laboratory.
26. Peter Fischer Ernst and Carol Lipson (1988). Thinking about science : Max Delbrück and the origins of molecular biology. New York: Norton. ISBN 978-0-393-02508-8.
27. K. R. Dronamraju (November 1999). "Erwin Schrödinger and the origins of molecular biology". Genetics. 153 (3): 1071–6. doi:10.1093/genetics/153.3.1071. PMC 1460808. PMID 10545442. from the original on April 28, 2012. Retrieved July 22, 2012.
28. M. P. Murphy and L. A. J. O'Neill (1997). What Is Life? the Next Fifty Years: Speculations on the Future of Biology. Cambridge University Press. p 2. ISBN 0-521-59939-3
29. Horace Freeland Judson (1996) The Eighth Day of Creation: Makers of the Revolution in Biology. Cold Spring Harbor Laboratory Press. ISBN 0-87969-478-5.
30. Kiryn Haslinger. Max Delbruck 100. September 23, 2015, at the Wayback Machine HT Winter 2007.
31. N. H. Horowitz (1994). "Review of kay, the Molecular Vision of Life: Caltech, the Rockefeller Foundation, and the Rise of the New Biology". Biophysical Journal. 66 (3 Pt 1): 929–930. Bibcode:1994BpJ....66..929H. doi:10.1016/S0006-3495(94)80873-2. PMC 1275794.

External links

 

Wikimedia Commons has media related to Max Delbrück.

 

Wikiquote has quotations related to Max Delbrück.

• Max Delbrück on Nobelprize.org  
• Delbrück page at Cold Spring Harbor Laboratory website.
• Letter from Jim Watson – Delbrück was instrumental in getting fellowship support for Watson so that he could stay in Cambridge, play tennis, and discover the rules of nucleotide base pairing in DNA. This is a letter from Watson to Delbrück that describes the discovery.
• Interview with Max Delbrück Oral History Project, California Institute of Technology Archives, Pasadena, California.
• The Official Site of Louisa Gross Horwitz Prize
• Key Participants: Max Delbrück – Linus Pauling and the Race for DNA: A Documentary History
• National Academy of Sciences Biographical Memoir