Hans Krebs (biochemist)

Hans Krebs with wife 1953

Lady Churchill, Hans Krebs, Frits Zernike 1953

Hans Adolf Krebs (25 August 1900 – 22 November 1981) was a German-born British biochemist best known for his identification of the citric acid cycle, also known as the Krebs cycle. This pivotal discovery in the field of biochemistry earned him the Nobel Prize in Physiology or Medicine in 1953, which he shared with Fritz Albert Lipmann, the discoverer of coenzyme A, for their work on the intermediary metabolism of carbohydrates and fatty acids.

Early Life and Education

Hans Krebs was born in Hildesheim, Germany, to a Jewish family. His father, Georg Krebs, was an ear, nose, and throat surgeon who instilled in his son an early interest in medical science. Krebs began his education at the University of Göttingen in 1918, studying medicine. He later transferred to the University of Freiburg and then to the University of Berlin, where he completed his medical degree in 1925.

Career and Research

After receiving his medical degree, Krebs began his career in research under the tutelage of Otto Warburg at the Kaiser Wilhelm Institute for Biology in Berlin-Dahlem. It was here that Krebs developed an interest in cellular metabolism. In 1933, due to the rise of the Nazi regime and its anti-Semitic laws, Krebs, being Jewish, was forced to leave Germany. He moved to England, where he continued his research at the University of Cambridge under Sir Frederick Gowland Hopkins, a recipient of the Nobel Prize for his discovery of vitamins.

Krebs's most significant contribution to biochemistry was his discovery of the citric acid cycle in 1937, while he was working at the University of Sheffield. This cycle is a crucial metabolic pathway that catalyzes the oxidation of carbohydrates, fats, and proteins into carbon dioxide and water, thereby generating energy-rich molecules like ATP (adenosine triphosphate) and NADH (nicotinamide adenine dinucleotide). This discovery not only advanced the understanding of cellular metabolism but also laid the groundwork for future research in cellular respiration and energy production.

In addition to the citric acid cycle, Krebs also discovered the urea cycle, another important metabolic pathway, with his student Kurt Henseleit in 1932. This cycle is essential for the removal of ammonia, a toxic byproduct of amino acid metabolism, from the body.

Later Years and Legacy

Krebs continued his research and teaching career at the University of Sheffield and later at the University of Oxford until his retirement in 1967. Throughout his career, he received numerous awards and honors in addition to the Nobel Prize, including being knighted by Queen Elizabeth II in 1958.

Hans Krebs passed away on 22 November 1981 in Oxford, England. His legacy lives on through the Krebs cycle, a fundamental concept in biochemistry and biology that continues to be a critical area of study in understanding cellular metabolism and energy production.

See Also

• Citric acid cycle
• Nobel Prize in Physiology or Medicine
• Biochemistry
• Metabolism