Erwin Chargaff
1905-
American Biochemist
Erwin Chargaff has been a pioneer in the study of the chemical nature of nucleic acids. Chargaff's work proved that, contrary tothe prevailing views about nucleic acids in the 1940s, DNA was actually a complex and highly variable molecule that could serve as the genetic material. He also established the relationships, now known as "Chargaff's rules," among the four bases found in DNA.
Chargaff was born in 1905 in Czernowitz, which at the time was a provincial capital of the Austrian monarchy. His parents, Hermann Chargaff and Rosa Silberstein Chargaff, had been moderately well off, but they were financially ruined during the Great Inflation after World War I. As a child, Chargaff was a voracious and eclectic reader. In 1914, at the outbreak of World War I, his family was forced to move to Vienna to avoid the Russian occupation of Czernowitz. Chargaff received most of his education at the Maximiliansgymnasium in Vienna. He enjoyed school and excelled in literature and the classical languages. Chargaff, who is well known for his literary style, remembers having a special relationship to language ever since his childhood.
At the University of Vienna, Chargaff decided to major in chemistry. His dissertation dealt with organic silver complexes and the action of iodine on azides. Eventually, he was able to utilize some aspects of his thesis research in identifying the presence of sulfur-containing amino acids on paper chromatographs. While at the university, he met his future wife, Vera Broido. After Chargaff received his doctoral degree in 1928, he obtained a research fellowship at Yale University, where he worked with Rudolph J. Anderson on the lipids of tubercle bacilli. Chargaff and Vera Broido were married in New York in 1929 and returned to Europe in 1930. Their son was born in 1938.
Between 1930 and 1933 Chargaff carried out further research on tubercle bacilli at the University of Berlin's Institute of Hygiene. Chargaff was involved in the investigation of the "Lübeck scandal," which involved the prosecution of several physicians who had caused the deaths of several babies by using cultures of virulent tubercle bacilli instead of BCG vaccine. Chargaff's work helped to prove that BCG itself had not been responsible for the disaster. In 1933 Albert Calmette (1863-1933) invited Chargaff to work at the Pasteur Institute. One year later, Chargaff returned to the United States to work at the Mount Sinai Hospital in New York, before accepting a research position in the department of biochemistry at Columbia University, where he carried out research on the biochemistry of blood coagulation. He also studied lipids, lipoproteins, phospholipids, inositols, hydroxy amino acids, and conducted the first synthesis of a radioactive organic compound. Chargaff remained at Columbia for the rest of his professional career. He became an assistant professor at 33, an associate professor at 41, and a professor at 47. He retired in 1974 and is currently Professor Emeritus and Special Lecturer in Biochemistry and Molecular Biophysics.
In 1944 Chargaff read Oswald T. Avery's (1877-1955) famous paper on the transforming principle and became convinced that DNA was the "hereditary code-script." He had recently read Erwin Schrödinger's (1887-1961) What Is Life? and was already thinking about the biochemical nature of genes. The combined impact of Avery's paper and Schrödinger's book convinced Chargaff to study nucleic acids. Work previously carried out by Phoebus Aaron Levene (1869-1940) suggested that DNA was a repetitious polymer, but Chargaff disproved that assumption by conducting precise analyses of nucleic acids from many sources, such as beef thymus, spleen, liver, human sperm, yeast, and tubercle bacilli. Using methods that first became available after World War II—paper chromatography, UV spectrophotometry, and ion-exchange chromatography—he proved that the four bases were not present in equal amounts, contrary to Levene's "tetranucleotide hypothesis." Chargaff called attention to the noteworthy fact that in all DNA molecules the molar ratios of total purines to total pyrimidines, and, more specifically, the ratios of adenine to thymine and of guanine to cytosine, were about one. The meaning of this "regularity" could not be determined at the time, but it was later explained in terms of the complementarity rules of the DNA double helix.
Chargaff was elected to the National Academy of Science in 1965. His voluminous writings include a two-volume work called The Nucleic Acids (1955, 1960), Essays on Nucleic Acids (1963), Voices in the Labyrinth (1977), and the autobiographical Heraclitean Fire (1978). Although the Nobel Committee has failed to acknowledge his crucial work on the biochemistry of DNA, he was awarded the National Medal of Science in 1975. At the end of the twentieth century, Chargaff was still actively thinking about science and the meaning of life, as indicated in his essay "In Dispraise of Reductionism," which was published in the journal Bioscience in 1997. Here, he analyzed issues related to the term "reductionism" and their implications for science.
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