Blauer G
Arch Biochem Biophys. 1986 Nov 15;251(1):315-22. doi: 10.1016/0003-9861(86)90079-2.
Light absorption and circular dichroism (CD) were recorded at 26 to 27 degrees C in dilute aqueous solutions (10(-4) M) of ferriprotoporphyrin IX (FP) in the presence of (+)-quinidine. In contrast to the appearance of relatively small and positive CD bands between pH 7 and 10, two bands of opposite sign, having unusually large molar ellipticities of the order of 10(6) deg X cm2 X dmol-1 FP were observed in the Soret region near 400 nm at pH 11.0-11.5. This unique complex A was formed only slowly over periods of hours or days at 26 degrees C. By lowering the pH of Complex A below 10, under certain conditions, an "enantiometric" mirror-image CD spectrum, with all bands having opposite sign to Complex A, was obtained in the range of 650 to 300 nm (Complex B), while the light-absorption spectra of Complexes A and B were similar. The formation of Complex A was inhibited at mole fractions of FP greater than 0.5. Also, this complex was not measurably formed at low salt concentrations. Ultracentrifugation measurements of the complex solutions indicated the presence of very high aggregates. Possible interpretations of the optical properties observed are based on interactions between FP molecules, which are assumed to be arrayed chirally within aggregates of FP with quinidine. A comparison between quinine and quinidine complexes of FP is presented.
在26至27摄氏度下，于高铁原卟啉IX（FP）的稀水溶液（10⁻⁴ M）中，在（+）-奎尼丁存在的情况下记录光吸收和圆二色性（CD）。与pH值在7至10之间出现相对较小的正CD带不同，在pH值为11.0 - 11.5时，在400 nm附近的Soret区域观察到两个符号相反的带，其摩尔椭圆率异常大，约为10⁶ deg·cm²·dmol⁻¹ FP。这种独特的复合物A在26摄氏度下仅需数小时或数天的时间缓慢形成。在特定条件下，将复合物A的pH值降至10以下，在650至300 nm范围内可获得“对映体”镜像CD光谱，所有谱带的符号与复合物A相反（复合物B），而复合物A和B的光吸收光谱相似。当FP的摩尔分数大于0.5时，复合物A的形成受到抑制。此外，在低盐浓度下无法检测到该复合物的形成。对复合物溶液的超速离心测量表明存在非常高的聚集体。观察到的光学性质的可能解释基于FP分子之间的相互作用，假定这些分子在手性排列的FP与奎尼丁的聚集体中排列。本文还对FP的奎宁和奎尼丁复合物进行了比较。
