If chymotrypsin molecule undergoes a ser-195-ala mutation then :
Serine- 195 is a highly reactive residue of chymotrypsin molecule.It endows chymotrypsin with its 'Reactivity' and not its ability to bind to substrate. In absence of Ser- 195 residue, chymotrypsin is inactivated i.e., it will not cleave, however, it still has the ability to bind (by viue of other remaining residues).
Chymotrypsin will not bind the substrate
Chymotrypsin will bind the substrate as well as cause cleavage
Chymotrypsin will bind the substrate but will not cause cleavage
No affect will be observed