The Power of Phosphate

This paper concerns the development of a central tenet of modern biochemistry: that cellular metabolism coordinates biological energy supply through the cyclical making and breaking of “energy-rich” phosphate bonds. This interpretation of intermediary metabolism was comprehensively set forth in two review articles published nearly simultaneously (though independently) in early 1941 by German biochemist Fritz Lipmann and Danish biochemist Herman Kalckar. Lipmann and Kalckar first met in the early 1930s in Copenhagen, where they were in frequent contact until 1939, when both left Denmark. Despite the similar claims advanced in Lipmann’s and Kalckar’s reviews, the two men’s presentations differed substantially with respect to their descriptions of “energy-rich” phosphate bonds and their target audiences. In order to explore the circumstances behind these divergences, this paper utilizes a “parallel lives” approach. By analyzing Lipmann’s and Kalckar’s lives in parallel, particular institutional contexts emerge as having been especially significant in shaping their differing interpretations of the power of phosphate bonds. The period that Lipmann spent in muscle researcher Otto Meyerhof’s laboratory (1927–30) conditioned his physiological interpretation of the role of phosphate bonds in cellular energy metabolism. Kalckar’s time at California Institute of Technology (1939–40)—where he was in regular communication with chemists such as Linus Pauling—played the most significant role in his decision to present the power of phosphate bonds from a chemical perspective. Ultimately, an examination of the life stories behind Lipmann’s and Kalckar’s 1941 reviews illuminates how older physiological perspectives were combined with recent advances in theoretical chemistry to explain how energy flows through living organisms.