Reynolds J A, Tanford C
Proc Natl Acad Sci U S A. 1976 Dec;73(12):4467-70. doi: 10.1073/pnas.73.12.4467.
Sedimentation equilibrium measurements can be used to determine the molecular weight of the protein moiety of a protein-detergent complex without prior knowledge of detergent binding. The procedure is to adjust the solvent density by addition of D2O so as to blank out the contribution of bound detergent to the sedimentation potential. An approximate measure of detergent binding can be obtained from the effect of solvent density on the sedimentation result. The procedure is also applicable to protein-lipid complexes. It can be used for complexes containing both lipid and detergent if the lipid content is known. The use of the method is demonstrated by experimental data for the AI polypeptide of serum high density lipoprotein, in separate complexes with nonionic detergents and with a phospholipid.
沉降平衡测量可用于在无需事先了解去污剂结合情况的前提下,测定蛋白质 - 去污剂复合物中蛋白质部分的分子量。具体步骤是通过添加重水来调节溶剂密度,从而消除结合去污剂对沉降电势的贡献。可从溶剂密度对沉降结果的影响中获得去污剂结合的近似度量。该方法也适用于蛋白质 - 脂质复合物。如果已知脂质含量,它可用于同时含有脂质和去污剂的复合物。通过血清高密度脂蛋白的AI多肽与非离子去污剂及磷脂形成的单独复合物的实验数据,展示了该方法的应用。