Question

Proteinaceous nature of enzyme was suggested by

• A. T. Cech
• B. Kuhne
• C. E. Buchner
• D. Northrop

Answer 1

The correct option is D Northrop

Enzymes are biological catalysts. The multitude of biochemical reactions that make cellular metabolism possible are due to enzymes. The isolation and crystallization of urease by James Sumner in 1926 provided a breakthrough in early enzyme studies. Sumner found that urease crystals consisted entirely of protein, and he postulated that all enzymes are proteins. In the absence of other examples, this idea remained controversial for some time. Only in the1930s, was Sumners conclusion widely accepted, after John Northrop and Moses Kunitz crystallized pepsin, trypsin, and other digestive enzymes and found them also to be proteins.