James B. Sumner

The great scientist James B. Sumner was born on 19 November 1887 in Canton, Massachusetts. At age 17 while hunting , he was accidentally shot by a companion and he lost his arm from just below the elbow. He had been left handed before that accident but after that he had to learn to do things with right hand.  

Sumner graduated in 1910 from Harvard University where he was educated with some conspicuous chemists. After a little period of working in the cotton knitting factory, he started his teaching career. In 1914 he obtained his PhD degree in biochemistry with Otto Folin. Then he worked as assistant professor of biochemistry. 

In 1917 at Cornell Where he began his research of isolation of enzymes in pure form. He worked with urease, which he isolated from jack beans. Sumner's work was unsuccessful for many years so his colleagues were doubtful upon his work, but in 1924 he demonstrated the isolated and crystallized enzyme urease. He achieved this by using purified urease with acetone and then cooled it, that solution produced crystallized urease. He was also able to prove that his pure urease was a protein. This was the first experimental proof that an enzyme is a protein. 

In 1937, he started isolating and crystallizing a second enzyme , catalase. By this time, John Northrop had obtained other crystalline enzymes By similar methods. It had become clear that Sumner's method of general crystallization of enzymes and the statement that all enzymes are protein. For crystallization of enzymes, Sumner , Northrop and Wendell M. Stanley shared the Nobel prize in 1946.

Akanksha Joshi,

Microbiol,

RSML