2.3.1.199 additional information the 3-ketoacyl-CoA reductase, KAR, the enzyme catalyzing the next step in metabolism after fatty acid elongase ELOVL6, largely stimulates ELOVL6 activity. Activity of purified enzyme ELOVL6 is enhanced by about 3fold in the presence of 3-ketoacyl-CoA reductase, KAR. This effect is KAR enzyme activity-independent, since it is observed in the absence of NADPH and in the poorly active or inactive KAR mutants, overview. ELOVL6 enzyme activity is also enhanced in a KAR enzyme activity-dependent manner 737127 2.3.1.199 NADPH ELOVL6 activity in membrane fractions is enhanced in the presence of NADPH 737127