Husain M, Stankovich M T, Fox B G
Biochem J. 1984 May 1;219(3):1043-7. doi: 10.1042/bj2191043.
Potentiometric titrations of pig liver electron-transfer flavoprotein (ETF) were performed at pH 7.5 and 4 degrees C, both in the reductive and oxidative directions. Reduction of ETF to the hydroquinone form required a total of two reducing equivalents/mol of ETF with the formation of sub-stoichiometric amounts of anionic semiquinone as an intermediate. The oxidation-reduction potentials for the two one-electron couples, oxidized ETF/ETF semiquinone and ETF semiquinone/fully reduced ETF, are +4 mV and -50 mV respectively. The overall midpoint potential for the two-electron couple (oxidized ETF/fully reduced ETF) is -23 mV.
在pH 7.5和4℃条件下,对猪肝电子传递黄素蛋白(ETF)进行了电位滴定,滴定方向包括还原和氧化方向。将ETF还原为对苯二酚形式,每摩尔ETF总共需要两个还原当量,并形成亚化学计量量的阴离子半醌作为中间体。两个单电子对的氧化还原电位,即氧化态ETF/ETF半醌和ETF半醌/完全还原态ETF,分别为+4 mV和-50 mV。双电子对(氧化态ETF/完全还原态ETF)的整体中点电位为-23 mV。