Biochemistry Department, National Vegetable Research Station, CV 35 9EF, Wellesbourne, Warwicks.
Planta. 1985 May;164(2):272-7. doi: 10.1007/BF00396092.
The solubilised ethylene-binding site (EBS) of Phaseolus vulgaris L. cotyledons is an asymmetrical protein with a sedimentation coefficient of 2 S and a Stoke's radius of 6.1 nm (determined by ultracentrifugation on isokinetic gradients and gel-permeation chromatography, respectively). The molecular weight and frictional ratio were calculated as 52 000-60 000 and 2.37-2.48, respectively. The EBS has an isoelectric point at between pH 3-5, determined by isoelectric focussing and exhibits a negative charge at pH 8 during non-denaturing electrophoresis. The electrical charge on the EBS is shielded; the EBS does not bind to anion-exchange media under the experimental conditions reported here, is not precipitated by ammonium sulphate and does not precipitate at its isoelectric pH. The EBS preferentially partitions into detergent phases. The results indicate that the EBS is a hydrophobic protein complexed with detergent in aqueous solution. The techniques used to characterise the EBS also resulted in varying degress of purification.
菜豆子叶中已溶解的乙烯结合部位（EBS）是一种不对称蛋白质，沉降系数为 2S，Stoke's 半径为 6.1nm（分别通过等速梯度超速离心和凝胶渗透层析测定）。分子量和摩擦比分别计算为 52000-60000 和 2.37-2.48。EBS 的等电点在 pH 3-5 之间，通过等电聚焦测定，在非变性电泳时在 pH 8 时带负电荷。EBS 的电荷被屏蔽；在本报告的实验条件下，EBS 不会与阴离子交换介质结合，不会被硫酸铵沉淀，也不会在等电 pH 沉淀。EBS 优先分配到去污剂相中。结果表明，EBS 是一种与去污剂结合的疏水性蛋白质复合物，在水溶液中。用于表征 EBS 的技术也导致了不同程度的纯化。
