Herman Kalckar
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Herman Moritz Kalckar | |
|---|---|
 | |
| Born | 26 March 1908 |
| Died | 17 May 1991 (aged 83) |
| Education | University of Copenhagen |
| Known for | Recognition of ATP as a universal energy carrier |
| Awards | Honorary degrees from |
| Scientific career | |
| Fields | Biochemistry |
| Institutions | |
| Doctoral advisor | Ejnar Lundsgaard |
| Other academic advisors | Fritz Lipmann |
| Notable students | James D. Watson |
Herman Moritz Kalckar (26 March 1908 – 17 May 1991) was a Danish biochemist who pioneered the study of cellular respiration.[1][2] Kalckar made a number of significant contributions to the development of 20th century biochemistry including:
- a founder of bioenergetics;
- enzymology, including novel assay techniques;
- galactose metabolism in both microorganisms and animal tissues;
- suggestion that strontium-90 levels in children’s deciduous teeth correlated with nuclear testing.[3]
Kalckar described his family life as “a middle class, Danish family—Danish for several generations.”[4] His family life was not financially wealthy but was intellectually rich. His father, Ludvig Kalckar, was a businessman with an avid interest in theatre, especially the work of Henrik Ibsen. His mother, Bertha (née Melchior) Rosalie introduced Kalckar to a variety of French and German writers, including Gustave Flaubert, Marcel Proust, Johann von Goethe, and Heinrich Heine. Kalckar observed that this time allowed his “interest in the humanistic disciplines” to develop and thrive.[5]
In his autobiographical reflections, Kalckar spent little time on his early education and referred to high school biology experience as "somewhat static," except for "some extraordinary demonstrations in human physiology" by August Krogh. Krogh, a physiologist and Professor at the University of Copenhagen, won the 1920 Nobel prize for his description of capillary blood flow and regulation, introduced the principles of human physiology to Danish high school students. Krogh's demonstrations introduced the students to a number of modern physiology instruments and experimental techniques.[6] The experience seems to have profoundly influenced Kalckar's choicer of research area.
Graduate Work
Kalckar completed his medical training at the University of Copenhagen in 1933, and then began research for his Ph.D. in Ejnar Lundsgaard's (1899–1968) physiology laboratory; that work established the foundation of a fundamental biochemical paradigm, i.e. "oxidative phosphorylation". During this period, Lundsgaard was preoccupied as physiology department chair, consequently Fritz Albert Lipmann, who had recently fled Germany,[7] served as Kalckar's research mentor. Later, Kalckar and Lipmann both independently developed concepts of a "high energy bond" (which Lipmann famously expressed as "~P") and ATP as a universal "energy carrier."[8]
Kalckar was fortunate to be working at an important period in biochemistry's evolution.[9][10] The biochemical community was in the process of demonstrating the chemical reactions involved in breakdown of foodstuffs essential for growth. At the same time, physiologists were demonstrating the involvement of some of these reactions various physiological processes, e.g. muscle contraction. Kalckar's breakthrough work was the demonstration that organic compounds, which were phosphorylated during metabolic processes, involved oxygen consumption; oxygen consumption was linked to organic compound phosphorylation. His key experiment demonstrated that in frog muscles where glycolysis had been inhibited with iodoacetate, muscular contraction continued for a short period using phosphocreatine as a source of energy.[11][12][13][14] Kalckar referred to this process as “aerobic phosphorylation” (now called oxidative phosphorylation, a biochemical process fundamental to all living organisms). The work was the first demonstration that carbohydrate oxidation and carbohydrate phosphorylation were linked, i.e. the two pathways were directly “coupled.” [15] Furthermore, the study helped establish the basic phenomenon of oxidative phosphorylation, opened the way for its systematic exploration, and suggested for the first time that phosphate compounds acted as a link between catabolism and anabolism.[16]
