What was the discovery for which Sumner was awarded Nobel Prize?

Explanation

**Step-by-Step Solution:**

1. **Identify the Nobel Prize Category and Year**: The question asks about the discovery for which J.B. Sumner was awarded the Nobel Prize. He received the Nobel Prize in Chemistry in the year 1946.

2. **Understand the Discovery**: The key discovery made by J.B. Sumner was that enzymes could be crystallized. This was significant because it demonstrated that enzymes, which are biological catalysts, could exist in a pure, solid form.

3. **Context of the Award**: It's important to note that the Nobel Prize was awarded in two halves. One half was awarded to J.B. Sumner for his discovery regarding enzymes, while the other half was jointly awarded to J.H. Northrop and W.M. Stanley for their work on the preparation of enzyme and virus proteins in pure form.

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