Sugimura Y, Yoshizaki F, Katagiri J, Horiuchi C
J Biochem. 1980 Feb;87(2):541-7. doi: 10.1093/oxfordjournals.jbchem.a132776.
Cytochrome b-561 (Enteromorpha prolifera) was extracted from a green alga, E. prolifera, by immersion of the dried thalli in phosphate buffer solution. Purification was carried out by ammonium sulfate fractionation, DEAE-cellulose and DEAE-Sephadex column chromatographies, Bio-Gel gel filtration, and hydroxyapatite column chromatography. The reduced form of the cytochrome exhibited absorption maxima at 561 (alpha), 530.5 (beta), and 428.5 nm (gamma), and the oxidized form at 530.5, 417 (gamma), and 275 nm. The alpha-band of the reduced form was symmetric without any shoulder. The pyridine hemochrome showed absorption maxima at 556, 524, and 418 nm. The cytochrome does not combine with carbon monoxide or cyanide. The cytochrome showed little peroxidase activity. The cytochrome is oxidized by ferricyanide and reduced by cysteine, ascorbate, and hydrosulfite. Ferrocyanide and hydroquinone do not completely reduce it. Autoxidation of the cytochrome was found to be very slow. The midpoint potential (Em) of the cytochrome was determined by equilibration with the ferro- and ferri-EDTA system to be +0.23 volt at pH 7.0 and 25 degrees C. The molecular weight of the cytochrome, estimated by Sephadex gel filtration, was 67 x 10(3).
细胞色素b - 561（浒苔）是通过将干燥的藻体浸泡在磷酸盐缓冲溶液中从绿藻浒苔中提取出来的。通过硫酸铵分级沉淀、DEAE - 纤维素和DEAE - 葡聚糖柱色谱、生物凝胶凝胶过滤以及羟基磷灰石柱色谱进行纯化。该细胞色素的还原形式在561（α）、530.5（β）和428.5 nm（γ）处呈现吸收最大值，氧化形式在530.5、417（γ）和275 nm处呈现吸收最大值。还原形式的α带是对称的，没有任何肩峰。吡啶血色素在556、524和418 nm处呈现吸收最大值。该细胞色素不与一氧化碳或氰化物结合。该细胞色素几乎没有过氧化物酶活性。该细胞色素可被铁氰化物氧化，并被半胱氨酸、抗坏血酸和连二亚硫酸盐还原。亚铁氰化物和对苯二酚不能完全将其还原。发现该细胞色素的自动氧化非常缓慢。通过与亚铁 - 和铁 - EDTA系统平衡，在pH 7.0和25℃下测定该细胞色素的中点电位（Em）为+0.23伏。通过葡聚糖凝胶过滤估计该细胞色素的分子量为67×10³。
