Why is melvin calvin important

Such discussion later involved James Franck, A. Krasnovsky, A. Terenin, George Porter, R. At Lewis's chemistry departmental research conferences in , he was soon known for his skill in asking important questions. Throughout his career, Melvin asked questions, seeking to know and understand his surroundings and the research being done in his laboratories.

As the radioautographs of the paper chromatograms Radiograms were developed, he tried to memorize their information, as well as the information related by the people doing the. Melvin usually finished his lectures and office and committee work about p. There was no letup. His coworkers had to keep some tidbits in reserve so they could always have something interesting to report.

When important chromatograms were exposed on X-ray film, they used two sheets, one to develop too early to appease Melvin's insatiable curiosity and one for proper documentation.

Among his skills were effective management of personnel, budgets, publications, consultancies, and presentations at important scientific conferences. Such skills engendered productive laboratories and enthusiastic collaboration of their scientists. Over the years Calvin's ever widening activities and responsibilities were efficiently managed through his office. Selection of the to visiting scientists and students, arranging for their schedules and research, handling the dozens of distinguished lectureships, and acceptances of honorary degrees from thirteen institutions consumed time, but he was a skilled planner and remarkably quick at making decisions.

Melvin Calvin was a fearless scientist, totally unafraid to venture into new fields like hot atom chemistry, carcinogenesis, chemical evolution and the origin of life, organic geochemistry, immunochemistry, petroleum production from plants, farming, moon rock analysis, and development of novel synthetic biomembrane models for plant photosysrems. By asking questions and quickly reading some books, he felt comfortable in many fields of endeavor. He stimulated and supported interdisciplinary thought and research among his colleagues.

The circular Melvin Calvin Laboratory, first occupied in , was designed to promote con-. The breadth of his interests and experience in chemical science served him well in his interactions with his colleagues, and he was clearly an awesome figure for visitors and students, whose experience was generally limited in scope.

It seemed that he had few peers who could criticize or analyze the impact of his ideas and projects. The primary limitation of his ideas stemmed from his limited experience in mechanics and practical laboratory techniques.

His energetic curiosity, however, overcame such limitations as he probed the experience of experts and soon became conversant with a new subject or the operating principle of a new instrument. Melvin was equally fearless in pursuing novel ideas. He had no qualms about suggesting experiments or publishing papers that further research soon undermined. The isolation of radioactive succinate from algae fed radioactive CO 2 in the dark, conditions where succinate accumulates, led to the suggestion for a C-4 cycle of photosynthetic carbon reduction.

The fact that such a cycle provided no useful information on photosynthetic carbon dioxide reduction didn't bother him a bit. The most exciting was his thioctic acid theory of photosynthesis, which consumed over a year's work by the group in the Old Radiation Laboratory.

As the several pillars of evidence began to fall, Melvin was unperturbed and went on to a new approach. Melvin's marvelous technique for delivering a scientific lecture was unique. His mind must have roamed constantly, especially in planning lectures. His remarkable memory enabled him to formulate a lecture or manuscript with no breaks in the sequence of his thoughts. His lectures usually began hesitatingly, as if he had little idea of how to begin.

This completely disarmed his audiences, who would try to guess what he might have to say. Soon enough, however, his ideas would coalesce, to be delivered like an approaching freight train, reaching a crescendo of information at breakneck speed and leaving his rapt audience nearly overwhelmed. One evening at a meeting of the American Association for the Advancement of Science, his novel theory of photosynthesis was so impressive that, when he finished, the great C.

It was a great theory, indeed. Melvin Calvin was a survivor. Against great odds, he enjoyed nearly fifty productive years after his frightening experience of a coronary during an Atomic Energy Commission site visit in He was thirty-eight years old; his father and uncle had succumbed to coronaries at age thirty-seven.

It was a sobering thought, indeed. With his wife Genevieve's determined efforts and his own, he lost 50 pounds, quit smoking, and after a year's convalescence continued the work he had set about to accomplish. Like so many aspects of his research, it was sheer good fortune that he should suffer a coronary in a room with a distinguished physician, Nathaniel Berlin, and next door to Jack Gofman, a physician and father of LDL and HDL serum lipoproteins and the consequent modern dietary concerns.

Clearly, Melvin's agile mind was working day and night, continuously churning through his data, plans, and deductions. Even the writing of a paper for publication was clearly the result of intense planning. His coauthor would meet him and his secretary at eight o'clock in the morning to find him pacing around the table, ready to dictate the manuscript, the technique he had learned from G. In an hour his part was finished, and he went off to deliver his.

Melvin Calvin was recruited by College of Chemistry and Chemical Engineering dean Wendell Latimer and Radiation Laboratory director Ernest Lawrence in to lead biological chemical efforts utilizing the newly available radioisotopes from Hanford and Oak Ridge National Laboratory in medical and photosynthesis research.

This followed the pioneering works of chemistry faculty member Sam Ruben and Radiation Laboratory staff chemist and physicist Martin Kamen. Department of State. There is no doubt that Ruben and Kamen unequivocally earned a Nobel Prize for their discovery of longlived radioactive carbon C, which engendered a revolution in humanity's understanding of biology and medicine.

Lawrence was understandably proud of his contribution to that discovery and, with his brother John Lawrence, was eager to continue support once the war was over.

In Ernest's words recollected by Melvin Calvin, It's time to do something worthwhile. The first programs centered on applications of C in medicine and synthesis of radio-labeled amino acids and biological metabolites for medical research in John Lawrence's Donner Laboratory and other laboratories across the country.

Calvin assembled a strong group of excellent chemists with biological interests. Its wooden building, the Old Radiation Laboratory, was released stepwise for Calvin's use for the photosynthesis research program, which interested Ernest Lawrence especially. To provide continuity with the Ruben-Kamen research efforts, Calvin invited Benson, then at Caltech to return to Berkeley to establish the laboratory and direct the photosynthesis research.

Benson had begun work on the path of carbon in photosynthesis as an instructor in the Department of Chemistry with Sam Ruben in , and research with carbon was well under way. Separation of the products by partition between immiscible solvents showed promise and, in the subsequent application of filter paper chromatography, involved the same principle.

Solvent partition was already a standard procedure in studies of the transuranium elements and their compounds. In spite of the advanced concepts of Ruben and Kamen, who brought the path of carbon into modern biochemistry, a major tenet of contemporary leaders, such as James Franck and Farrington Daniels, involved absorption of carbon dioxide and chlorophyll within some protein complex whereby the energy of a photoexcited state of chlorophyll could result in transfer of hydrogens from water to carbon dioxide.

The product formaldehyde could polymerize to sugar and release the oxygen as molecular oxygen gas. Even the products of dark fixation of 14 CO 2 had not clearly dispelled such theory.

Benson continued his isolation of the product of dark 14 CO 2 fixation and, for a time, with the near daily assistance of Edwin McMillan, crystallized the radioactive product soon identified as succinic. The unequivocal demonstration of non-photochemical reduction of CO 2 , however, involved illumination of algae in the absence of CO 2 instantly followed by transfer of the algae to black flasks containing 14 CO 2 Analysis of the products formed revealed production of radioactive sucrose at rates approaching those in the light.

Clearly, the energy absorbed by chlorophyll was used for production of phosphorylating and reducing agents capable of driving the conversion of CO 2 to sugar. That phrase, coined by Melvin Calvin, was used in the title of twenty-four publications.

As designed by Sam Ruben, experiments to discern the first product of CO 2 fixation necessarily required examination of products of shorter and shorter times of exposure to 14 CO 2. Such experiments were not easily accomplished with the low-specific activity C 2.

The far higher specific activities available in from Hanford and Oak Ridge reactions, however, rendered such experiments feasible. With the introduction to the Old Radiation Laboratory of paper chromatographic techniques by W. Stepka from the Department of Plant Nutrition, short-time 5 seconds 14 CO 2 fixations could be resolved and appeared to produce only one major labeled product. Melvin Calvin had introduced the new Duolite A-3 anion exchange resin to the project.

They found that the labeled compound eluted far less readily than sugar monophosphates from the resin on the column. Logically, Calvin attributed this to its having. Such a category included phosphoglyceric acid with its phosphate and carboxylate anionic groups. One may get the impression that Melvin was never a hands-on chemist. Not true! When they were down to the wire with the first product of CO 2 fixation, it was Melvin with the latest information on anion exchange resin from Dow Chemical who pushed identification of the unknown compound.

Recrystallization failed to remove its radioactivity. The first product of CO 2 fixation, then, was three-carbon phosphoglyceric acid PGA , a long-known product of glucose fermentation with its carboxyl group containing the radioactivity, following the general reaction outlined six years earlier by Ruben and Kamen.

The competing laboratory of James Franck, Hans Gaffron, and colleagues at the University of Chicago failed to confirm this discovery and engendered a polemic in the literature greatly enhancing the inner tensions of Melvin Calvin. A symposium planned by Farrington Daniels to decide which laboratory was following the correct path was held in Chicago under auspices of the American Association for the Advancement of Science.

Calvin and Benson traveled by train, as was Calvin's practice at that time, to present their procedures and results before a huge audience. At first, the Chicago group refused to acquiesce, but it soon recognized its failure and the polemic was defused. With the first product identified as a known metabolite, the remaining members of the glycolytic sequence were identified by their chemical behavior.

The prior labeling of fructose confirmed the predicted sequence of reactions. Two sugars separated on the paper chromatograms intrigued Benson, who examined their reactivities and recognized them as ketoses. With the able collaboration of James A. Bassham the compounds were subjected to periodate degradation.

Benson doubly labeled the smaller of the sugars with 32 P and 14 C and measured their ratio, 2 phosphorus atoms to 5 carbon atoms. The pentose diphosphate could have few possible structures and they were identified radiochromatographically.

Still, there was no indication of the two-carbon precursor of phosphoglycerate. This lists the logos of programs or partners of NG Education which have provided or contributed the content on this page.

Leveled by. Friday, January 21, The Calvin cycle is a process that plants and algae use to turn carbon dioxide from the air into sugar , the food autotrophs need to grow. Every living thing on Earth depends on the Calvin cycle. Plants depend on the Calvin cycle for energy and food. Other organisms, including herbivores, like deer, depend on it indirectly.

Herbivores depend on plants for food. Even organisms that eat other organisms, like tigers or sharks, depend on the Calvin cycle. For centuries, scientists knew that plants could turn carbon dioxide and water into sugar carbohydrates using light energy—a process called photosynthesis.

Fifty years ago, biochemist Dr. Melvin Calvin figured out the photosynthetic process from his lab at the University of California at Berkeley, located in the United States.

The Calvin cycle is named after Dr. Green algae are aquatic organisms that use photosynthesis. By this method, he discovered the steps plants use to make sugar out of carbon dioxide.

Steps in the Calvin Cycle The Calvin cycle has four main steps. Energy to fuel chemical reactions in this sugar-generating process is provided by ATP and NADPH , chemical compounds that contain the energy plants have captured from sunlight.

In step one, a carbon molecule from carbon dioxide is attached to a 5-carbon molecule called ribulose biphosphate RuBP. The method of attaching a carbon dioxide molecule to a RuBP molecule is called carbon fixation. The 6-carbon molecule formed by carbon fixation immediately splits into two, 3-carbon molecules called 3-phosphoglycerate 3-PGA. In step two, 3-PGA is converted into glyceraldehydephosphate G3P , a chemical used to make glucose and other sugars.

Creating G3P is the ultimate objective of the Calvin cycle. In step three, some of the G3P molecules are used to create sugar. Glucose, the type of sugar produced by photosynthesis, is composed of two G3P molecules. In step four, the G3P molecules that remain combine through a complex series of reactions into the 5-carbon molecule RuBP, which will continue in the cycle back to step one to capture more carbon from carbon dioxide.

The key to understanding what was going on in the chloroplast came to him one day while "waiting in my car while my wife was on an errand ," he said. Calvin realized the way in which plants turn carbon dioxide into sugar wasn't a straightforward one.

Instead, it worked in a circular pattern. For discovering how plants turn carbon dioxide into sugar, Calvin was awarded the Nobel Prize for chemistry in Bush in He published his autobiography , Following the Trail of Light , in He died on January 8, , in Berkeley, California. Understanding the Calvin Cycle Understanding how the Calvin cycle works is important to science in several ways.

Today, the U. These findings were described in Chemical Evolution He was author of over publications and held a number of patents. He served on many scientific boards for the United States government, including the President's Science Advisory Committee for presidents Kennedy and Johnson. In he received the Nobel Prize in chemistry for his work on the path of carbon in photosynthesis.

The Royal Society awarded him the Davy Medal in for his pioneering work in chemistry and biology, particularly the photosynthesis studies. Despite his important contribution to chemistry and biology, Calvin continued to involve himself in research. In the s, as the shortage of the world's oil fuel supply was brought into sharp perspective by the Arab Oil Embargo, he began to contemplate the possibility of alternative nature-based fuels.

From a farm in Northern California, he began testing the practicality of his theory: that a plantation growing certain species of rubber trees that secrete a sap with characteristics similar to petroleum, could produce enough of this sap to constitute a viable alternative fuel source. After retiring from the University of California, Calvin continued to be honored from his scientific peers, receiving the American Chemical Society's Priestly Medal in and that organization's Oesper Prize in There is no full-length biography of Calvin.

Melvin Berger's, Famous Men of Modern Biology , written in nontechnical language, contains a section on Calvin that emphasizes his work in photosynthesis. William Gilman, Science: U. A useful background source is John F.