Dixon作图法和双倒数作图法都表明TTFA有两个抑制位点.低浓度下(0-20μmol/L)的高亲和位点对Q_2呈非竞争性,高浓度下(20μmol/L以上)的低亲和位点呈竞争性.由此得出结论:泛醌还原的两步反应均被TTFA抑制,低浓度时只抑制后半步从半醌还原成氢醌的反应,高浓度时对从泛醌到半醌以及半醌到氢醌两个半反应都抑制. Dixon mapping and double reciprocal mapping both showed that TTFA had two inhibitory sites.High affinity (0-20μmol / L) high affinity sites were noncompetitive to Q_2 at high concentration (20μmol / L Above) .Therefore, it was concluded that the two-step reaction of ubiquinone reduction was inhibited by TTFA, while only the inhibition of the half-quinone reduction from half-quinone to hydroquinone at the low concentration, the high concentration Both ubiquinone to semi-quinone and semi-quinone to hydroquinone two half-reactions were inhibited.