The controversy over the minimum quantum requirement for oxygen evolution

During the early- to mid-twentieth century, a bitter controversy raged among researchers on photosynthesis regarding the minimum number of light quanta required for the evolution of one molecule of oxygen. From 1923 until his death in 1970, Otto Warburg insisted that this value was about three or four quanta. Beginning in the late 1930s, Robert Emerson and others on the opposing side consistently obtained a value of 8–12 quanta. Warburg changed the protocols of his experiments, sometimes in unexplained ways, yet he almost always arrived at a value of four or less, except eight in carbonate/bicarbonate buffer, which he dismissed as “unphysiological”. This paper is largely an abbreviated form of the detailed story on the minimum quantum requirement of photosynthesis, as told by Nickelsen and Govindjee (The maximum quantum yield controversy: Otto Warburg and the “Midwest-Gang”, 2011); we provide here a scientific thread, leaving out the voluminous private correspondence among the principal players that Nickelsen and Govindjee (2011) examined in conjunction with their analysis of the principals’ published papers. We explore the development and course of the controversy and the ultimate resolution in favor of Emerson’s result as the phenomenon of the two-light-reaction, two-pigment-system scheme of photosynthesis came to be understood. In addition, we include a brief discussion of the discovery by Otto Warburg of the requirement for bicarbonate in the Hill reaction.     

On the requirement of minimum number of four versus eight quanta of light for the evolution of one molecule of oxygen in photosynthesis: A historical note

A bitter controversy had existed as to the minimum number of quanta required for the evolution of one molecule of oxygen in photosynthesis: Otto Warburg had insisted since 1923 that this value was 3–4, whereas Robert Emerson and others continued to obtain a value of 8–12 since the 1940s. It is shown in this letter that the 1931 Nobel-laureate of Physiology & Medicine Otto Warburg published, in his last and final paper, just before his death in 1970, a measured minimum quantum requirement of oxygen evolution of 12 at the lowest intensities of light he used. Although using his theory on photolyte, Warburg calculated a value of 3–4 for the quantum requirement, this is the first confirmation by Warburg of the higher measured quantum requirement. However, it has remained unknown to most investigators. It is expected that this information will be of general interest not only to those interested in the history and research on photosynthesis, but to the entire sci entific community, especially the writers of text books in biology, biochemistry and biophysics.     

On Otto Warburg,Nazi Bureaucracy and the difficulties of moral judgment

Twentieth-century photosynthesis research had strong roots in Germany, with the cell physiologist Otto H. Warburg being among its most influential figures. He was also one of the few scientists of Jewish ancestry who kept his post as a director of a research institution throughout the Nazi period. Based on archival sources, the paper investigates Warburg’s fate during these years at selected episodes. He neither collaborated with the regime nor actively resisted; he was harrassed by bureaucracy and denunciated to the secret police, but saved by powerful figures in economy, politics, and science. Warburg reciprocated this favour with problematic testimonies of political integrity after 1945. Warburg’s case, thus, defies wellestablished notions of how scientists in Germany lived and worked during the Nazi regime, and, therefore, helps provide a more nuanced perspective on this theme.     

Charles Stacy French: A tribute

Charles Stacy French, one of the great men of photosynthesis research, died on 13 October 1995. He received his PhD at Harvard University where he associated with William Arnold, Caryl Haskins, later president of the Carnegie Institution of Washington, and Pei-Sung Tang. He did early work on the photosynthesis of photosynthetic bacteria with Robert Emerson and later with Otto Warburg. French worked for three years with James Franck in Chicago. His associates there included Hans Gaffron, Robert Livingston, Warren Butler and Roderick Clayton. After spending three years at the University of Minnesota he became the director of the Department of Plant Biology of the Carnegie Institution of Washington and remained there until he retired in 1973. French's research career at the Carnegie Institution was marked by the development of novel and ingenious pieces of equipment such as the French pressure cell used to prepare chloroplast particles to measure partial reactions of photosynthesis. He developed the first recording fluorescence spectrophotometer and demonstrated efficient energy transfer between certain photosynthetically-active pigments, a spectrophotometer that measured the first derivative of absorbance, as well as a novel analog computer to show that complex absorption curves in living plants are produced by a number of distinct forms of chlorophyll occurring in vivo. French used the Blinks rate-measuring oxygen electrode to measure action spectra of oxygen evolution by photosynthesis automatically. He and Jack Myers did some of the pioneering work on the Emerson effect showing the necessary cooperation of two photosystems in photosynthesis. French used the Carnegie Institution's fellowship program to bring large numbers of scientists from around the world to his laboratory. When Stacy French died in 1995, the field of photosynthesis lost one of its great and early pioneers.This is CIW/DPB publication No. 1314.     

A comment on Warburg’s early understanding of biocatalysis

The early history of biochemistry was characterized by changing moods. The discovery of cell free fermentation (1897) led to the optimistic belief that all life processes were carried out by intracellular enzymes, being definite proteins with special catalytic properties. But, the persistent failure to isolate pure enzymes raised doubts. When Otto Warburg found cell respiration to be a membrane-bound iron catalysis (1914), he renewed the old position that biocatalysis was caused by surface forces and ferments could be heavy metal ions adsorbed on colloidal membrane carriers. This alternative view became popular when Warburg started his research in photosynthesis and explained his peculiar “photolyte” model. Neither the suggestion of surface-active colloidal ferments, nor the idea of “photolyte” stood the test of time and have now been rejected, but their history is of importance to how concepts evolve and die.     

Building the contractile ring from the ground up: a lesson in perseverance and scientific creativity

This contribution to the Festschrift for Professor Thomas (Tom) D. Pollard focuses on his work on the elucidation of the protein organization within the cytokinetic nodes, protein assemblies, precursors to the contractile ring. In particular, this work highlights recent discoveries in the molecular organization of the proteins that make the contractile machine in fission yeast using advanced microscopy techniques. One of the main aspects of Tom’s research philosophy that marked my career as one of his trainees is his embrace of interdisciplinary approaches to research. The cost of interdisciplinary research is to be willing to step out of our technical comfort zone to learn a new set of tools. The payoff of interdisciplinary research is the expansion our realm of possibilities by bringing new creative tools and ideas to push our research program forward. The rewarding outcomes of this work under Tom’s mentorship were the molecular model of the cytokinetic node and the development of new techniques to unravel the structure of multi-protein complexes in live cells. Together, these findings open a new set of questions about the mechanism of cytokinesis and provide creative tools to address them.     

Neuroscience was not even a word: an interview with Floyd Bloom

Floyd Bloom says that he grew up, surrounded by doctors and pills, in a drug store in Dallas, where his father and uncles were pharmacists. He is a natural storyteller, readily recalling the people and events that have shaped his career. His narrative skills were apparent as early as high school, where he was encouraged, partially on the basis of aptitude tests, to pursue a career in journalism or public relations, and to stay away from hard subjects like math and science. In college, he majored in German literature, although he pursued premedical studies in accordance with his father's wishes. During his medical school and residency experiences in St. Louis, he recounts, he always attempted to carry in his mind an organized way of explaining his academic and clinical activities to the professors and attending physicians that might quiz him. His subsequent research into the central nervous system similarly benefited from his ability not only to anticipate and formulate questions, the answers to which often required the development of new methods, technologies, and alliances, but also to place his findings in novel contexts where they could be conceptually appreciated and utilized. The prospect of telling good scientific stories was one of the factors that later drew Bloom to the position of Editor-in-Chief of Science magazine (1995-2000). While there, he was instrumental in widening the contexts in which the magazine presents science, and in shaping the ways that scientific information is electronically disseminated across the globe. Currently on sabbatical from Scripps, Floyd Bloom continues to explore, as CEO of a startup company in La Jolla, the entrepreneurial contexts in which his own research can be applied.     

August Rauber (1841-1917): from the primitive streak to Cellularmechanik

In the early 19th century Karl Ernst von Baer initiated a new research program searching for the mechanisms by which an egg transforms itself into an embryo. August Rauber (1841-1917) took up this challenge. He considered the phylogenetic principle as the right tool to explain the similitude of embryogenetic processes. In extending Baer's approach, he combined comparative embryology and histology in his studies of avian and mammalian embryos. His earlier work demonstrated that the two-layered chick embryo is a modified gastrula and not a "disc" as Wilhelm His had claimed. From the 1880s onwards, he concentrated on the issue of how the development of germ layers is related to tissue differentiation. To address this, he studied the blastopore, epiblast, primitive streak, teratology and the relative importance of nucleus and cytoplasm in heredity. This paper reconstructs some of Rauber's work and concludes that his observations and reflections constituted a new approach combining embryology and histology with "phylogenetic" reasoning.     

Martin Gibbs (1922–2006): Pioneer of 14C research, sugar metabolism & photosynthesis; vigilant Editor-in-Chief of Plant Physiology; sage Educator; and humanistic Mentor

The very personal touch of Professor Martin Gibbs as a worldwide advocate for photosynthesis and plant physiology was lost with his death in July 2006. Widely known for his engaging humorous personality and his humanitarian lifestyle, Martin Gibbs excelled as a strong international science diplomat; like a personal science family patriarch encouraging science and plant scientists around the world. Immediately after World War II he was a pioneer at the Brookhaven National Laboratory in the use of ¹⁴C to elucidate carbon flow in metabolism and particularly carbon pathways in photosynthesis. His leadership on carbon metabolism and photosynthesis extended for four decades of working in collaboration with a host of students and colleagues. In 1962, he was selected as the Editor-in-Chief of Plant Physiology. That appointment initiated 3 decades of strong directional influences by Gibbs on plant research and photosynthesis. Plant Physiology became and remains a premier source of new knowledge about the vital and primary roles of plants in earth’s environmental history and the energetics of our green-blue planet. His leadership and charismatic humanitarian character became the quintessence of excellence worldwide. Martin Gibbs was in every sense the personification of a model mentor not only for scientists but also shown in devotion to family. Here we pay tribute and honor to an exemplary humanistic mentor, Martin Gibbs.     

Is there a post-racism? On David Theo Goldberg’s conjunctural analysis of the post-racial

ABSTRACT

I comment on David Theo Goldberg’s Are We all Postracial Yet? by interpreting it as a programmatic essay towards a new conjunctural analysis of a globalizing racism, and as an emerging globalizing dialogue against racism. In the spirit of Goldberg’s book I relate these two modes of critical engagement in order to open a global perspective through which a relational understanding of racism can be formulated with respect to two neoliberal contexts, continental Europe and the United States. To this end I draw on the work of Étienne Balibar and in particular his early consideration of ‘neo-racism’.     

A biographical sketch of Charles F. Yocum: “It's the biochemistry, stupid”

Charles F. Yocum has been a leader in the applications of biochemical techniques to the resolution and reconstitution of Photosystem II. His formal science education began as an undergraduate in biochemistry at Iowa State University and continued with graduate work in photosynthesis, first at the Illinois Institute of Technology and later at Indiana University. Following postdoctoral work at Cornell University, he joined the faculty of the University of Michigan where he has remained throughout his academic career. Charlie's contributions to a biochemical understanding of photosynthesis, particularly Photosystem II have been considerable, but most notably include his initial isolation of the first highly active oxygen-evolving particle from higher plant chloroplasts, the well-known and widely utilized `BBY particles'. In the aftermath of that isolation, Charlie's research further resolved these particles into ever finer and simpler, but active, Photosystem II complexes. In addition, Charlie's research has provided significant insight into the roles of both Cl⁻ and Ca²⁺ as required cofactors in photosynthetic oxygen evolution. This revised version was published online in June 2006 with corrections to the Cover Date.     

Govindjee,an institution,at his 80th (really 81st) birthday in Třeboň in October, 2013: a pictorial essay

Govindjee (one name only), who himself is an institution, has been recognized and honored by many in the past for he is a true ambassador of “Photosynthesis Research” to the World. He has been called “Mr. Photosynthesis”, and compared to the Great Wall of China. To us in T?eboň, he has been a great research collaborator in our understanding of chlorophyll a fluorescence in algae and in cyanobacteria, and more than that a friend of the Czech “Photosynthesis” group, from the time of Ivan ?etlík (1928–2009) and of Zdeněk ?esták (1932–2008). Govindjee’s 80th (really 81st) birthday was celebrated by the Institute of Microbiology, Laboratory of Photosynthesis, by toasting him with an appropriate drink of a suspension of green algae grown at the institute itself. After my presentation, on October 23, 2013, of Govindjee’s contributions to photosynthesis, and his intimate association with the photosynthetikers (in Jack Myers’s words) of the Czech Republic, Govindjee gave us his story of how he began research in photosynthesis in the late 1950s. This was followed by a talk on October 25 by him on “Photosynthesis: Stories of the Past.” Everyone enjoyed his animated talk—it was full of life and enjoyment. Here, I present a brief pictorial essay on Govindjee at his 80th (really 81st) birthday in T?eboň during October 23–25, 2013.     

No evolution,no heredity,just development—Julius Schaxel and the end of the Evo–Devo agenda in Jena, 1906–1933: a case study

Julius Schaxel is an almost forgotten figure in the history of early twentieth century biology. By focusing on his life and work, I would like to illustrate several central developments in that period of history of biology. Julius Schaxel was an early representative and organizer of theoretical biology, discussing and criticizing both Wilhelm Roux’s mechanism and Hans Driesch’s vitalism. In addition to his theoretical work, Schaxel also did experimental research on developmental issues to support his critique. In this paper, special emphasis is made on the negotiating practice of Schaxel, which he used to establish a new area of biological research and a new audience for that area. In contrast to these new fields, Schaxel can be also portrayed as the endpoint of a research tradition investigating ontogeny and phylogeny together, which today is called Evo–Devo. Following Garland Allen’s dialectical processes that led to the decline of the Evo–Devo research agenda, Schaxel’s example is used to investigate these processes.     

Still going strong: Leeuwenhoek at eighty

At age 80, Antony van Leeuwenhoek was a world-famous scientist who came from a prosperous Delft family with a heritage of public service. He continued that tradition by serving in paid municipal offices. Self-taught, he began his scientific career in his 40s, when he began making hundreds of tiny single-lens microscopes. Pioneering the use of now-common microscopic techniques, he was the first human to see microbes and microscopic structures in animals, plants, and minerals. Over 50 years, he wrote only letters, more than 300 of them, and published half of them himself. More than a hundred were published in translation in the Royal Society’s Philosophical Transactions. Today, Leeuwenhoek is considered in the lesser rank of scientists and is not well known outside of his homeland. Recent archival research in Delft has contributed new information about his life that helps to contextualize his science, but much remains to be learned.     

A rendezvous with the queen of ion channels: Three decades of ion channel research by David T Yue and his Calcium Signals Laboratory

David T. Yue was a renowned biophysicist who dedicated his life to the study of Ca²⁺ signaling in cells. In the wake of his passing, we are left not only with a feeling of great loss, but with a tremendous and impactful body of work contributed by a remarkable man. David's research spanned the spectrum from atomic structure to organ systems, with a quantitative rigor aimed at understanding the fundamental mechanisms underlying biological function. Along the way he developed new tools and approaches, enabling not only his own research but that of his contemporaries and those who will come after him. While we cannot hope to replicate the eloquence and style we are accustomed to in David's writing, we nonetheless undertake a review of David's chosen field of study with a focus on many of his contributions to the calcium channel field.     

“A Massive Long Way”: Interconnecting Histories, a “Special Child,” ADHD, and Everyday Family Life

Focusing on one family from a study of dual-earner middle-class families carried out in Los Angeles, California, this article draws on interview and video-recorded data of everyday interactions to explore illness and healing as embedded in the microcultural context of the Morris family. For this family, an important aspect of what is at stake for them in their daily lives is best understood by focusing on 9-year-old Mark, who has been diagnosed with attention-deficit/hyperactivity disorder (ADHD). In this article, we grapple with the complexity of conveying some sense of how Mark’s condition is experienced and relationally enacted in everyday contexts. Through illuminating connections between lives as lived and lives as told, we explore the narrative structuring of healing in relation to Mark’s local moral world with the family at its center. We examine how his parents understand the moral consequences of the child’s past for his present and future, and work to encourage others to give due weight to his troubled beginnings before this child joined the Morris family. At the same time, we see how the Morris parents act to structure Mark’s moral experience and orient to a desired future in which Mark’s “success” includes an appreciation of how he is accountable to others for his actions. Through our analyses, we also seek to contribute to discussions on what is at stake in everyday life contexts for children with ADHD and their families, through illuminating aspects of the cultural, moral and relational terrain that U.S. families navigate in contending with a child’s diagnosis of ADHD. Further, given that ADHD is often construed as a “disorder of volition,” we seek to advance anthropological theorizing about the will in situations where volitional control over behavior is seen to be disordered.     

Warburg,me and Hexokinase 2: Multiple discoveries of key molecular events underlying one of cancers’ most common phenotypes,the “Warburg Effect”, i.e., elevated glycolysis in the presence of oxygen

As a new faculty member at The Johns Hopkins University, School of Medicine, the author began research on cancer in 1969 because this frequently fatal disease touched many whom he knew. He was intrigued with its viscous nature, the failure of all who studied it to find a cure, and also fascinated by the pioneering work of Otto Warburg, a biochemical legend and Nobel laureate. Warburg who died 1 year later in 1970 had shown in the 1920s that the most striking biochemical phenotype of cancers is their aberrant energy metabolism. Unlike normal tissues that derive most of their energy (ATP) by metabolizing the sugar glucose to carbon dioxide and water, a process that involves oxygen-dependent organelles called “mitochondria”, Warburg showed that cancers frequently rely less on mitochondria and obtain as much as 50% of their ATP by metabolizing glucose directly to lactic acid, even in the presence of oxygen. This frequent phenotype of cancers became known as the “Warburg effect”, and the author of this review strongly believed its understanding would facilitate the discovery of a cure. Following in the final footsteps of Warburg and caught in the midst of an unpleasant anti-Warburg, anti-metabolic era, the author and his students/collaborators began quietly to identify the key molecular events involved in the “Warburg effect”. Here, the author describes via a series of sequential discoveries touching five decades how despite some impairment in the respiratory capacity of malignant tumors, that hexokinase 2 (HK-2), its mitochondrial receptor (VDAC), and the gene that encodes HK-2 (HK-2 gene) play the most pivotal and direct roles in the “Warburg effect”. They discovered also that like a “Trojan horse” the simple lactic acid analog 3-bromopyruvate selectively enters the cells of cancerous animal tumors that exhibit the “Warburg effect” and quickly dissipates their energy (ATP) production factories (i.e., glycolysis and mitochondria) resulting in tumor destruction without harm to the animals.     

In memory of Achim Trebst (1929–2017): a pioneer of photosynthesis research

The life and work of Achim Trebst (1929–2017) was dedicated to photosynthesis, involving a wide span of seminal contributions which cumulated in more than five decades of active research: Major topics include the separation of light and dark phases in photosynthesis, the elucidation of photosynthesis by the use of inhibitors, the identification of the three-dimensional structure of photosystem II and its degradation, and an explanation of singlet oxygen formation. For this tribute, which has been initiated by Govindjee, twenty-two personal tributes by former coworkers, scientific friends, and his family have been compiled and combined with an introduction tracing the different stages of Achim Trebst’s scientific life.     

Remembering Otto Kandler (1920–2017) and his contributions

After a brief prologue on Otto Kandler’s life, we describe briefly his pioneering work on photosynthesis (photophosphorylation and the carbon cycle) and his key participation in the discovery of the concept of three forms of life (Archaea, Prokarya, and Eukarya). With Otto Kandler’s passing, both the international photosynthesis and microbiology communities have lost an internationally unique, eminent, and respected researcher and teacher who exhibited a rare vibrancy and style.