[溶菌酶晶体离子组成的X射线荧光研究]

[X-ray fluorescent study of the ionic composition of lysozyme crystals].

作者信息

Kachalova G S, Lanina N F, Morozov V N, Morozova T Ia, Shliapnikova E A, Atanasov B P

出版信息

Biofizika. 1995 Mar-Apr;40(2):274-82.

Abstract

The method of the studying of the ionic content in the protein crystals by X-ray fluorescence spectroscopy is proposed. The ionic content of the tetragonal glutaraldehyde--cross-linked lysozyme crystals in the 2- 11 pH range and upon the low and high ionic strengths is studied. The acid-base titration of the lysozyme crystals is carried out for determination of the pH-dependence of the net charge of the lysozyme molecule within protein crystal. It has been shown that ionic content in the protein crystal channels is determined mainly by the Donnan potential. The specific binding of the bromide-ions with lysozyme molecules is revealed and possible binding sites are discussed.

摘要

提出了用X射线荧光光谱法研究蛋白质晶体中离子含量的方法。研究了四方晶系戊二醛交联溶菌酶晶体在2 - 11pH范围内以及低离子强度和高离子强度下的离子含量。对溶菌酶晶体进行酸碱滴定，以确定蛋白质晶体内溶菌酶分子净电荷的pH依赖性。结果表明，蛋白质晶体通道中的离子含量主要由唐南电位决定。揭示了溴离子与溶菌酶分子的特异性结合，并讨论了可能的结合位点。