ASA- acetylates PTGS1

The ionized form of aspirin, acetylsalicylate (ASA-) reacts spontaneously with one subunit of PTGS1 dimer to acetylate serine residue 516. The modified enzyme is no longer capable of catalyzing the conversion of arachidonate to PGH2. The identity of the acetylated residue is inferred from data for the humann PTGS2 enzyme (Lecomte et al. 1994) and the ovine PGHS1 enzyme (Loll et al. 1995).

阿司匹林的离子形式，即乙酰水杨酸（ASA-），会自发地与PTGS1二聚体的一个亚基反应，从而乙酰化丝氨酸残基516。经过修饰的酶已无法催化花生四烯酸转化为PGH2。乙酰化残基的身份推断自humann PTGS2酶的数据（Lecomte等，1994年）以及绵羊PGHS1酶的数据（Loll等，1995年）。