You have just graduated from the University of the West Indies and have applied to an international biotechnology company.  As part of their prescreening process they send you a tutorial which reads:

In your first week of work, your benchmate approaches you with a problem.  Using a site-directed mutagenesis kit, she has been generating mutants of the enzyme lysozyme.  One of her mutants (Glu³⁵ ® Ala³⁵ ) shows virtually no activity, while two others, (Asp⁵² ® Phe⁵²) and (Asp¹⁰¹ ® Gly¹⁰¹ + Trp⁶² ® His⁶² ) show reduced activity compared with the wild type enzyme.  She is concerned about the lack of activity of these enzymes.  Explain to her, as thoroughly as you can, why her mutants probably behave as observed.  Further, outline what modifications you might suggest making to the wild type enzyme to enhance activity.