Lipase, as its name suggests, is an enzyme responsible for the cleavage of types of lipid molecules. There are different types of lipases, many of which work in similar ways. For instance, Human Pancreatic Lipase, or HPL, splits triglycerides, the main lipids in the human diet, into glycerol and three fatty acids. The structure shown at right is that of Horse Pancreatic Lipase. It consists of two identical subunits, totaling 449 amino acids each.
The of lipase (just one subunit) include 102 residues which create 13 alpha helices, shown in black, and 139 residues involved in beta sheets totaling 28 strands, shown in red. Lipase of course consists of both
. The polar residues in this scene are shown in a light blue shade, and the nonpolar are in a dark red. From this representation, it can be assumed that there is a higher quantity of polar residues than nonopolar.