Holmquist L
King Gustaf V Research Institute, Karolinska Institute, Stockholm, Sweden.
Biomed Chromatogr. 1989 Nov;3(6):276-8. doi: 10.1002/bmc.1130030612.
Highly purified monomeric human plasma lecithin:cholesterol acyltransferase (LCAT), completely free of apolipoprotein D, has been chromatographed on a MonoQ HR 5/5 anion exchanger. LCAT eluted as symmetrical peaks after 12.8 min and 14.8 min at pH 5.0 and pH 6.0, respectively, using a linear NaCl gradient. The corresponding concentrations of NaCl effecting desorption of LCAT from the anion exchanger were 125 mM and 175 mM. At both pH values human serum albumin eluted earlier and was well separated from the enzyme. Rechromatography of LCAT in the eluates from these experiments at acid pH, on high performance gel filtration, demonstrated absence of aggregation. The nonspecific adsorption during anion exchange chromatography at pH 5.0 and pH 6.0 was negligible, as demonstrated by a linear relationship between injected amounts of LCAT and recorded peak areas for a 2-20 micrograms protein range. Zone immunoelectrophoresis assay indicated unaltered immunoreactivity of the eluted LCAT.
胆固醇酰基转移酶（LCAT），完全不含载脂蛋白D，已在MonoQ HR 5/5阴离子交换柱上进行了层析。使用线性NaCl梯度，在pH 5.0和pH 6.0条件下，LCAT分别在12.8分钟和14.8分钟后以对称峰形式洗脱。使LCAT从阴离子交换剂上解吸的相应NaCl浓度分别为125 mM和175 mM。在这两个pH值下，人血清白蛋白洗脱较早，且与该酶分离良好。在酸性pH条件下，将这些实验洗脱液中的LCAT进行高效凝胶过滤再层析，结果表明不存在聚集现象。在pH 5.0和pH 6.0进行阴离子交换层析时，非特异性吸附可忽略不计，在2 - 20微克蛋白质范围内，注入的LCAT量与记录的峰面积之间呈线性关系，证明了这一点。区带电泳分析表明洗脱的LCAT免疫反应性未改变。
