Hans Adolf Krebs was a British physician and biochemist who contributed significantly to the study of cellular respiration, a metabolic system in cells that produces energy. Krebs effectively discovered two crucial chemical reactions in the body, the urea cycle and the citric acid cycle, throughout the course of his more than five-decade career. While collaborating with Henseleit on the first, he continued to believe in employing a manometer to monitor oxygen use and identify chemical reactions in glucose metabolism. Krebs developed the glyoxylate cycle, a modest modification of the citric acid cycle found in plants, bacteria, protists, and fungi, with Hans Kornberg. The discovery of acetyl CoA by Fritz Lipmann was significant in defining the intricacies of the critical synthesis phase in the cycle. As a result, in 1953, the duo was awarded the Nobel Prize in Physiology or Medicine. Krebs held key academic positions in addition to his scientific activities. In 1934, he was named Demonstrator in Biochemistry at the University of Sheffield. He was elevated to the position of Lecturer in Pharmacology in 1935. He became the first Head of the Department of Biochemistry at the University of Sheffield in 1938, and Professor in 1945.
Childhood and Adolescence
Hans Adolf Krebs was born on August 25, 1900, in Hildesheim, Germany, to Georg and Alma Krebs. His father practiced otolaryngology (ear, nose, and throat surgery). Krebs was the second of the couple’s three children to be born.
Krebs was quiet and introverted as a child, but he was also hardworking and well-organized. He had a strong appreciation for architecture, as well as music, poetry, literature, and art. He was a nature lover who enjoyed flora collection as a hobby. He also practiced the piano.
Krebs received his official education at the renowned old Gymnasium Andreanum. He was a good student who excelled in numerous areas, with history being his favorite.
Krebs planned to follow in his father’s footsteps and become an ENT surgeon when he was fifteen years old. He began reading medical texts and hoped to train under his father before practicing independently.
In September 1918, when World War I broke out, he was recruited into the Imperial German Army. He was six months away from finishing his secondary studies at the time. The battle ended two months later, and so did Krebs’ subscription.
Krebs followed his ambition and enrolled at the University of Göttingen to study medicine in December 1918. He was transferred to the University of Freiburg the following year. Krebs grew interested in research during his time in university.
Krebs met Wilhelm von Mollendorf, a pioneer in the field of vital staining, for the first time in 1920. Krebs researched the effects of various colors on muscle tissue under Mollendorf’s supervision. His first technical work on tissue staining technique was published in 1923.
Krebs was certain of pursuing a scientific career by the time he finished his medical school in 1923. Nonetheless, he intended to pursue a career in internal medicine in order to support himself. Krebs earned his medical license after spending a year at the University of Berlin’s Third Medical Clinic in 1924.
Krebs merged clinical practice and experimental work while at the University of Berlin. He soon realized, however, that he had the capacity to be a powerful independent investigator and decided to pursue medical research in the subject of chemistry. In 1924, he studied in the Department of Chemistry at the Charité Hospital’s Pathological Institute in Berlin for the same purpose. He received his M.D. from the University of Hamburg the following year.
Career of Hans Adolf Krebs
Krebs began his work at the Kaiser Wilhelm Institute for Biology in Dahlem, Berlin, in 1926 as a research assistant to eminent biochemist Otto Heinrich Warburg. Krebs learned about tissue slicing and manometric methods for measuring the rate of respiration and glycolysis of cancer cells while interning with Warburg.
Krebs thought of using manometric tissue slicing techniques to examine intermediate metabolism after learning them. He recognized that little was known about the series of reactions that occur between the foodstuffs that enter the body and their final decomposition products, and he believed that by using the technique, he could link the unbroken sequences of chemical equations and thus bring about a biochemistry revolution. The concept, however, did not appeal to Warburg, and Krebs shelved it for the time being.
Krebs had been with Warburg for four years when he left in 1930. During that time, he produced approximately 16 publications. With Warburg’s skills no longer required, Krebs went into clinical medicine as an assistant in the Department of Medicine at the Municipal Hospital in Altona, despite his lack of conviction in conducting independent investigations. He moved to the University of Freiburg’s Medical Clinic the following year.
Krebs pursued a clinical and research career at Freiburg. He looked after 40 patients while also working with Kurt Henseleit, a fellow research student, to propose the urea production metabolic pathway. They conducted multiple studies that only proved that amino acids and ammonia can make urea in isolated liver slices and no other animal tissues, contrary to popular notion that amino acids and ammonia produce urea in the liver.
The ornithine cycle of urea synthesis, often known as the Krebs-Henseleit cycle, was discovered by Krebs and Henseleit. They began researching a possible method for synthesizing arginine. They combined a slice of liver with pure ornithine and citrulline using the Warburg manometer. Citrulline worked as a catalyst in the metabolic processes of urea from ammonia and carbon dioxide as a result of this discovery. Krebs and Henseleit announced their discoveries in 1932, establishing the ornithine cycle. The metabolic cycle was the first to be discovered.
Krebs’ scientific development came to a terrible halt in 1933. Following Hitler’s rise to power, he enacted the Law for the Restoration of the Professional Civil Service, which barred all non-Aryans and anti-Nazis from professional positions. Krebs was one of many Jews who were fired from university positions.
After being fired from his employment, Krebs was offered a position at the University of Cambridge’s Department of Biochemistry by Sir Frederick Gowland. The Rockefeller Foundation provided him with financial assistance.
Krebs was named a Demonstrator in Biochemistry in 1934. The University of Sheffield gave him a position as a Lecturer in Pharmacology the following year. He was in charge for 19 years.
The Department of Biochemistry at the University of Sheffield was established in 1938, and Krebs was appointed as its first Head and eventually professor in 1945.
Krebs partnered with William Johnson while at the University of Sheffield. Together, they looked into cellular respiration, which is the process of using oxygen to make energy from the breakdown of glucose. They conducted studies using a manometer for four months before ultimately determining the sequence of the chemical cycle, which they named the ‘citric acid cycle.’
Hans Adolf Krebs received the Nobel Prize in Physiology or Medicine in 1953 for “discovering the citric acid cycle.”
Krebs and Hans Kornberg teamed in 1957 and discovered that there were other important enzymes. They found the glyoxylate cycle, which was a modification of the citric acid cycle, by adding extra features.
Krebs excelled academically in addition to his scientific work. He became control of the Sorby Research Institute in 1943. He was named Director of the newly founded MRC Unit for Cell Metabolism Research in Sheffield a year later. He became Whitley Professor of Biochemistry at the University of Oxford in 1954. He held this position until 1967, when he retired. After retiring, Krebs spent the last two decades of his career trying to figure out why organisms oxidized their food in such a complicated way. Only in 1981 did Jack Baldwin respond to his question, indicating that acetic acid could not be immediately dehydrogenated and that oxidative decomposition required the addition of another molecule.
Major Projects of Hans Adolf Krebs
The discovery of two major chemical reactions in the body, the urea cycle and the citric acid cycle, was Krebs’ most significant contribution in his scientific career. For the first, he worked with Henseleit to discover the Krebs-Henseleit cycle, which is used to describe the ornithine cycle of urea production.
In 1937, he discovered the citric acid cycle, which was the pinnacle of his career. The oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins into carbon dioxide and chemical energy in the form of guanosine triphosphate was a series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins into carbon dioxide and chemical energy in the form of guanosine triphosphate (GTP). In 1953, he was awarded the Nobel Prize in Physiology or Medicine for his discovery.
Achievements & Awards
Krebs was awarded the Nobel Prize in Physiology or Medicine in 1953 for his discovery of the citric acid cycle. Fritz Lipmann and he shared the prize. He was awarded the Albert Lasker Award for Basic Medical Research the same year.
He was awarded the Royal Society’s Royal Medal in 1954.
He was awarded the Gold Medal of the Dutch Society for Physics, Medical Science, and Surgery in 1958. He was knighted the same year.
He was awarded the Copley Medal in 1961.
In 1980, he was awarded Honorary Membership by the Society for General Microbiology, which he founded.
Personal History and Legacy
On March 22, 1938, Hans Adolf Krebs married Margaret Cicely Fieldhouse. The couple had three children: Paul and John, two sons, and Helen, a daughter.
Kerbs died on November 22, 1981, in Oxford, following a brief illness.
Hans Krebs Tower is the name of the Department of Biochemistry building at the University of Oxford.
The Krebs Institute, a research center providing interdisciplinary programs in biochemical research, was founded by the University of Sheffield in 1988.
The Sir Hans Krebs Lecture and Medal was established by the Federation of European Biochemical Societies in 1990. The prize honors scientists who have made significant contributions to biochemistry and molecular biology.
The Sir Hans Krebs Prize, worth 10,000 euros, is awarded by the Society of Friends of Hannover Medical School.
The Krebs Memorial Scholarship is awarded by the Biochemical Society to a postgraduate student studying biochemistry or a related biomedical field at any British university.
Estimated net worth
The estimated net worth of Hans Adolf Krebs is unknown.