TABLE 2.

Catalytic activity and reaction specificity of human ALOX15 Q294L and Asn-287 mutants

Recombinant expression of human ALOX15, enzyme purification, product preparation, and HPLC analysis were performed as described under “Materials and Methods.” Equal amounts of enzyme were used, products (15-HETE + 12-HETE) were quantified for each sample, and the wild-type ALOX15 was set at 100%. For each mutant, three independent activity assays were carried out, and the means ± S.D. are given in the Table. ND, not determined because of lack of sufficient material. NS, not significant versus wild-type enzyme.

LOX species	Relative catalytic activity	Share of 15-HETE
	%	%
Wild-type	100 ± 5.8	89.0 ± 0.1
Q294L	0.6 ± 0.05	ND
N287L	0.5 ± 0.07a	ND
N287D	1.1 ± 0.3b	88.8 ± 0.2 (NS)
N287Q	3.9 ± 0.1	88.1 ± 1.2 (NS)

^a p = 0.007 (versus N287Q).

^b p = 0.016 (versus N287Q).