2.5.1.109	E108D	mutant loses at least 92% of its activity	722446	
2.5.1.109	E108G	mutant loses at least 92% of its activity	722446	
2.5.1.109	R122G	mutant with less than 2% catalytic activity	722446	
2.5.1.109	R122H	mutant with less than 2% catalytic activity	722446	
2.5.1.109	W424G	mutant loses more than 98% of its activity	722446	
2.5.1.109	W424Y	mutant retains about 25% of its activity	722446