Sandbox 49
From Proteopedia
| 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. |
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Introduction
Lipases represent a critical class of enzymes that functions in the breakdown of triacylglycerides. Produced by the pancreas, lipase catalyzes the hydrolysis of triacylglyercols at their 1 and 3 carbons, resulting the in the production of 2-monoacylglycerols and free fatty acids. Modeled here is horse pancreatic lipase.
Structure
Lipase has 449 amino acid resiudes, and 2 domains, the is smaller with 112 residues, and the consists of 337 residues. Notice that each of these domains consist of 2 identical subunits. Lipase has an a chain and a b chain that each respectively contain 1 of the subunits of the C Terminal Domain and 1 of the subunits of the N terminal domains, all 4 parts come together to form the fully functional enzyme.
The secondary structural elements of Lipase, including the that make up 30 percent of the amino acid chain, and involving 139 residues as well as the that make up 22 percent and 102 residues characterize the structure of the protein.
Important for the tertiary structure of the protein, are several different factors that function to hold each of the domains together in the proper orientation, the certainly make a difference as one might expect, since all proteins generally fold to shield these from interaction with water, the cysteine residues that Lipase has also play a major role since they form , Lipase has 12 disulfide bonds in all.
Lipase also has a that noncovalently binds to residues: Glu 187, Arg 190, Asp 192, Asp 195. There is one Calcium ion bound per chain in the enzyme. The catalytic groups are protected by a flap that folds over the are when a substrate is bound, aiding in the catalytic function of the enzyme.
References
- http://www.brenda-enzymes.org/php/result_flat.php4?ecno=3.1.1.3
- http://enzyme.expasy.org/cgi-bin/enzyme/enzyme-search-ec
- http://www.pdb.org/pdb/explore/explore.do?structureId=1HPL
- Fundamentals of Biochemistry, Voet
- http://www.uniprot.org/uniprot/P29183
