Question

People with the rare metabolic disorder lysinuric protein intolerance cannot properly digest proteins. Which of the following enzymes may be defective in this disorder? hint: think about protein digestion?

1. trypsin
2. carboxypeptidase
3. maltase
4. salivary amylase
5. gastric lipase

Answer 1

Trypsin.

Step-by-step explanation:

Trypsin is a peptidase or protease enzyme, which breaks the peptide bonds of proteins by hydrolysis to form smaller peptides and amino acids. Actually, it's an enzime that catalyzes the breaking down process of proteins.

Trypsin is produced in the pancreas and secreted in the duodenum (part of the intestine), where it is essential for digestion.

So, basically, trypsin is the enzyme among the options that intervenes in the proteins breaking down process, making it smaller which produces aminoacids.

Therefore, the right answer is Trypsin, because it's the enzyme responsible for the digestion of proteins molecules.

Answer 2

1. Trypsin

Step-by-step explanation:

The question states that the in the lysinuric protein intolerance disorder, people cannot properly digest proteins due to a defective enzyme involved in protein digestion.

Gastric lipase breaks down lipids.

Salivary amylase catalyzes the hydrolysis of starch into sugars.

Maltase breaks down maltose into two monomers of glucose.

Carboxypeptidase are proteases enzymes though most of them are not involved in protein digestion.

Trypsin is a protease found in the digestive system, that cleaves peptide chains at the amino acids lysine or arginine, involved in the lysinuric intolerance.

So, for the question´s purpose the right answer is 1, Trypsine.

But it´s important to notice that this disorder has been well studied and the known cause is not at the protein break down level, but at the transportation of lysine, arginine and ornithine amino acids between cells in the body. If we supplied affected people with this amino acid, they would still be unable to assimilate them.