Pepsins

Pepsins are a group of digestive enzymes that play a crucial role in the breakdown of proteins within the stomach. They belong to the class of enzymes known as proteases, which catalyze the hydrolysis of peptide bonds, facilitating the digestion of dietary proteins into smaller peptides and amino acids. Pepsins are primarily produced in the stomach lining by cells known as chief cells and are initially secreted as inactive precursors called pepsinogens. When exposed to the acidic environment of the stomach (pH 1.5-2.0), pepsinogens are converted to active pepsins.

These enzymes operate optimally at low pH levels and are resistant to acid, which allows them to function effectively in the stomach. Pepsins initiate protein digestion by cleaving peptide bonds at specific amino acid residues, particularly those involving aromatic amino acids such as phenylalanine, tryptophan, and tyrosine. This activity complements other proteases produced later in the digestive process, such as trypsin and chymotrypsin, which operate in the more neutral environment of the small intestine.

Pepsins are essential for efficient nutrient absorption and overall digestion. Their activity is regulated tightly to prevent excessive breakdown that could damage the stomach lining. Deficiencies or dysregulation of pepsin production can lead to digestive issues, such as malabsorption or gastritis.

Historically, pepsin extracts have been used in medicinal and industrial applications, including treatment of digestive disorders and protein hydrolysis in food processing. Modern research continues to explore the potential roles of pepsins and related enzymes in health sciences and biotechnology.