Question

Compare and contrast the general structure and function of active sites for two different enzymes—one which digests fats, and one which digests polysaccharides

Answer 1

We can compare the general structure and function of active sites of lipases( fat digesting enzymes) and amylases ( polysaccharide digesting enzymes) . The active site is the region of an enzyme where substrate molecules bind and undergo a chemical reaction. The active siteconsists of residues that form temporary bonds with the substrate (binding site) and residues that catalyse a reaction of that substrate (catalytic site). The active site of typical lipases contains a catalytic triad involving a serine residue, which takes part in the formation of an acyl-enzyme intermediate during the reaction . Most of the lipases operate at lipid–water interfaces enabled by a mobile lid domain located over the active site. Lid protects the active site and hence responsible for catalytic activity. In amylases domain A houses the active site and contains three catalytic residues:Asp197, Glu233, and Asp300. The neon structures are GLC sugars used for crystallography purposes and demonstrate the binding region. Hydrophobic ligands Arg337, Arg195 and Asn298 function as binding sites for chloride ions.