Trypsin. Computer model of part of a molecule of the digestive enzyme trypsin. Atoms are colour- coded: carbon (orange), nitrogen (blue) and oxygen (red). Trypsin is released by the pancreas. It is a protease, breaking down proteins into smaller chains of amino acids. It is released in an inactive form (trypsinogen) and converted to trypsin in the small intestine by the action of the enzyme enterokinase.