The main purpose is to be able to reuse the expensive catalyst of a particular reaction. If the enzyme is very cheap it may not be worth immobilising it. An immobilised enzyme is easily removed from a reaction mixture. Immobilised enzyme systems are easily controlled. In medical applications, immobilised enzymes cannot enter the circulation of the patient.
Protein design is the construction of entirely novel proteins.
The purpose of this tutorial is to reinforce the amino acid structures and to think about protein stability and enzyme activity and specificity. It is a beta-sheet as alternate side chains are found on the same side. The corresponding mutation in the serine protease subtilisin decreases the enzyme activity a million-fold. The enzyme stability may decrease a moderate amount as two hydrogen bonds are lost. 2L Enzyme activity will be similarly lost.