The Krebs cycle, also known as the citric acid cycle or the tricarboxylic acid cycle was discovered by Sir Hans Adolf Krebs, (born Aug. 25, 1900, Hildesheim, Ger.—died Nov. 22, 1981, Oxford, Eng.), German-born British biochemist who received (together with Fritz Lipmann) the 1953 Nobel Prize for Physiology or Medicine.
Krebs was educated at the Gymnasium Andreanum at Hildesheim and between the years 1918 and 1923 he studied medicine at the Universities of Göttingen, Freiburg-im-Breisgau, and Berlin.
At the University of Sheffield of England, Dr. Krebs and William Johnson published the work that led to the discovery of the citric acid cycle. These studies were performed in the pigeon breast muscle, which is the powerful muscle necessary for flight. This was a particularly good model as this muscle maintained its oxidative capacity after its disruption and suspension in aqueous media.
In 1937 Hans Krebs was able to present a complete picture of an important part of metabolism—the citric acid cycle. The Krebs cycle reactions involve the conversion—in the presence of oxygen—of substances that are formed by the breakdown of sugars, fats, and protein components to carbon dioxide, water, and energy-rich compounds. In the Krebs cycle, acetate, originating from the degradation of sugars or fatty acids, is further degraded to carbon dioxide, thereby yielding energy in the form of ATP and GTP molecules.
In 1945, only one element was missing from the cycle, the 2-carbon compound. A German-American biochemist, Fritz Lipmann identified it as a coenzyme – a molecule that when attached to a specific molecule forms an active enzyme. It was named Coenzyme A – “A” for the activation of acetate in the Krebs cycle.
The citric acid cycle brought Dr. Krebs international fame, and it is considered to this day his greatest scientific achievement.
Discovery of Krebs cycle by German biochemist, Hans Adolf Krebs
Papain in Papaya Juice: A Natural Remedy for Digestive Health
-
Papaya juice is highly regarded for its health benefits, with a key feature
being its high concentration of papain enzymes. Papain is a proteolytic
enzyme—...