Hans Adolf Krebs was a German-born British physician and biochemist who made significant contribution in the study of cellular respiration, a biochemical pathway in cells for production of energy. In his more than five decades of career, Krebs successfully discovered two important chemical reactions in the body, the urea cycle and the citric acid cycle. While for the first he collaborated with Henseleit, for the second he carried on his belief of detecting oxygen consumption and identifying chemical reaction in glucose metabolism using manometer. Together with Hans Kornberg, Krebs discovered the glyoxylate cycle, which was a slight variation of the citric acid cycle found in plants, bacteria, protists, and fungi. It was Fritz Lipmann’s discovery of acetyl CoA that helped specified the details of the crucial synthetic step in the cycle. As a result, the duo was bestowed with the Nobel Prize in Physiology or Medicine in 1953. Apart from scientific career, Krebs held important academic posts. He was appointed as Demonstrator in biochemistry at the University of Sheffield in 1934. In 1935, he was promoted to the post of Lecturer in Pharmacology. In 1938 when University of Sheffield opened a Department of Biochemistry, he served as its first Head, and eventually Professor in 1945.