Designed as a handout for college-level biology classes. Click on the image for the full-sized version. All enzymes are listed under the regions of the alimentary canal where they are active. Places they are produced are discussed below.
A brief overview of the enzymes discussed here:
- Oral Cavity
- (salivary) amylase -- produced in the salivary glands, hydrolyzes starch into disaccharides (namely maltose)
- pepsin -- produced in an inactive form, pepsinogen, by chief cells in the gastric glands (in the stomach lining), it is then activated in the lumen by hydrochloric acid and previously present pepsin. Breaks polypeptides (unfolded proteins) into smaller polypeptides.
- Small Intestine
- pancreatic amylase -- produced in the pancreas, hydrolyzes polysaccharides into disaccharides.
- trypsin -- produced in the pancreas, hydrolyzes peptide amide bonds in polypeptides (thus breaking polypeptides into smaller polypeptides), especially when they contain lysine or arginine.
- chymotrypsin -- produced in the pancreas, very similar to trypsin in that it hydrolyzes amide bonds; however, it preferentially attacks polypeptides containing tyrosine, tryptophan, and phenylalanine.
- lipase -- produced in the pancreas, hydrolyzes fat molecules into fatty acids and glycerol.
- carboxypeptidase -- produced in the duodenum, cleaves single amino acids off of polypeptide chains from the carboxy-terminal end.
- nucleases -- produced in the pancreas, these enzymes break down nucleic acids into their component nucleotides.
- maltase -- produced in the duodenum, hydrolyzes maltose into the monosaccharide glucose.
- sucrase -- produced in the duodenum, hydrolyzes sucrose into the monosaccharides glucose and fructose.
- lactase -- produced in the duodenum, hydrolyzes lactose into the monosaccharides glucose and galactose.