James B. Sumner, American chemist and academic, Nobel Prize laureate (d. 1955)

James Batcheller Sumner (November 19, 1887 – August 12, 1955) was an American chemist. He discovered that enzymes can be crystallized, for which he shared the Nobel Prize in Chemistry in 1946 with John Howard Northrop and Wendell Meredith Stanley. He was also the first to prove that enzymes are proteins.