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Please do NOT make changes to this Sandbox. Sandboxes 30-60 are reserved for use by Biochemistry 410 & 412 at Messiah College taught by Dr. Hannah Tims during Fall 2012 and Spring 2013.

Lipase is a hydrolase that catalyzes the breakdown of lipids by hydrolyzing the esters of fatty acids. Lipases are important in digestion, promoting absorption of fats in the intestines. Lipase is primarily found in the pancreas but is also found in the mouth and the stomach. Pancreatic lipase which is pictured below catalyzes the hydrolysis of triacylglycerols at the 1 and 3 positions to from 1,2-diacylglycerols and 2-acylglycerols. Pancreatic liapase consists of two identical chains, totaling 449 residues.

Lipase Secondary Structure

spinqualitylabelsall models Structure of HMG-CoA reductase (PDB entry 1HPL) Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image The two identical chains of lipase are pictured in blue-gray and green. Lipase has a consisting of 22% alpha helices, which are shown in blue, and 30% beta sheets, which are shown in bright green. The rest of the secondary structure consists of ordered, nonrepetitive structure. Lipase also contains six disulfide bonds which are illustrated by the yellow rods. Lipase contains three important which are highlighted in yellow. These three catalytic residues are all located in the A chain and consist of Ser 152, Asp 172, and His 263. Serine functions to form a covalent bond to the ester, forming a tetrahedral intermediate. Aspartate and histidine function in acid-base catalysis by accepting and donating hydrogen atoms to stabilize the reaction.

Ligand Interaction Pancreatic lipase is shown here in a complex with the coenzyme colipase, which enhances lipase's function. The two identical lipase chains are pictured in pink and blue. The two identical chains of colipase are pictured in yellow and green. Three ligands are shown in association with the two lipase chains. Two calcium ions are shown in green as space-filling balls. Beta-mercaptoethanol is also shown as yellow, grey, and red balls. Lastly, (hydroxyethyloxy)tri(ethyloxy)octane is pictured as the larger grey, white, and red ball cluster.