Edwin G. Krebs

Edwin and Deedy remained together till his death in 2007. They had three children, Sally Herman, Robert Krebs and Martha Abrego.

Krebs led a very active life till he was almost eighty years old. In 1997, he finally closed his laboratory at the University of Washington. Even after that he attended research seminars on regular basis and was keenly interested in latest development in the field.

Edwin Gerhard Krebs was born in June 6, 1918, in Lansing, Iowa. His father, William Carl Krebs, was a Presbyterian minister, while his mother, Louise Helen (Stegeman) Krebs, was a teacher before her marriage. Edwin was third of his parents’ four children.

Because of his father’s profession, they were required to move around a lot. Finally, in and around 1924, they settled in Greenville, Illinois. The town had good schools and Edwin enjoyed his life immensely.

He was a good student and also liked hiking, fishing, stamp collecting. Some time now, he made a ham radio just to keep in touch with a friend who had moved to Chicago.

In 1933, William Carl Krebs, died unexpectedly. At that time, Edwin was studying in the first year of the high school and his elder brothers were at the University of Illinois. To cut cost, his mother moved the family to Urbana and Edwin was enrolled at Urbana High School.

Financially, it was a hard time. To make the ends meet, Edwin, like his brothers, took up part time job. At the same time, he began contemplating about his future. Both chemistry and medicine appealed to him because he believed it would be easier to earn his living with them.

Edwin G. Krebs earned his medical degree in 1943 and joined Barnes Hospital, also in St. Louis, for 18-month residency. On its completion, he joined the US Navy as a medical officer on active duty as part of the war service.

In 1946, Krebs was discharged from Navy. Although he wanted to join hospital duty he did not get the scope immediately. Subsequently, he joined Washington University at St. Louis and began to work on the interaction of protamine with rabbit muscle phosphorylase under Carl and Gerty Cori, as postdoctoral fellow.

Krebs’ postdoctoral period came to an end in 1948. By that time he had made up his mind to continue research work. Therefore, when the offer came, he happily joined the University of Washington, Seattle as an Assistant Professor at the Department of Biochemistry.

He first started working on DPNH-X, a derivative of NADH. But when in 1953, Edmond H. Fischer arrived at the university ‘the two Eds’ started working on the enzymology of phosphorylase. As the emphasis in the department was on protein chemistry and enzymology, it provided an excellent environment for their work.

It is to be remembered that before he came here, Krebs had worked with the Coris on phosphorylase on rabbit muscle phosphorylase. There they had found that, for the phosphorylase to function, AMP had to serve as some kind of co-factor.

Krebs is best known for his work on reversible protein phosphorylation, a biochemical mechanism that regulates the activities of the cells. He began his studies with Edmond H. Fischer to find out how muscles get their energy from glycogen and what role AMP had in phosphorylation.

By the middle of the 1950s they discovered that phosphorylation and dephosphorylation of proteins are regulated by enzymes. A kinase enzyme called protein kinase moves a phosphate group from adenosine triphosphate (ATP) to a protein. This activates the protein and it starts taking part in the biological reactions.

When the job is done, a protein phosphatase deactivates the protein by removing the phosphate. The process regulates a number of biological functions such as mobilization of glucose from glycogen, prevention of transplant rejection, development of a cancer like chronic myeloid leukemia etc.