Which enzyme converts trypsinogen into trypsin?

The enzyme that converts trypsinogen into trypsin is enterokinase. Enterokinase, also known as enteropeptidase, is secreted by the cells of the intestinal mucosa and plays a crucial role in the digestive process. When trypsinogen, which is an inactive precursor (or zymogen) produced by the pancreas, enters the small intestine, enterokinase activates it by cleaving a specific peptide bond. This activation is essential because trypsin is necessary for the digestion of proteins; it breaks down polypeptides into smaller peptides.

The process highlights the importance of enzyme activation in the digestive system, ensuring that enzymes are only active when they reach the correct environment (in this case, the small intestine) to prevent them from digesting proteins in the pancreas or other tissues beforehand. This careful regulation is vital for maintaining proper digestive health and function.