Background
	To study the branching enzyme, we performed several 
mutations on the branching enzyme gene.  A mutation is a change 
in the DNA sequence of the gene which gives a change in the amino 
acid sequence it encodes.  When the mutant protein is produced, 
information can be obtained from a study of changes compared to 
the wild type expression.  For example, in the branching enzyme, 
the mutations effected the activity of the enzyme.  Such changes 
in the catalytic efficiencies indicate that the amino acids might 
be important in catalysis.
	For enzymes, the structure determines function.  Site 
directed mutagenesis can help us understand the structure 
function relationship of the enzyme.