当前位置： SCI文献检索 > BIOPHYSICAL JOURNAL期刊下所有文献 > How Hofmeister ion interactions affect protein stability.

How Hofmeister ion interactions affect protein stability.

Abstract：

:Model compound studies in the literature show how Hofmeister ion interactions affect protein stability. Although model compound results are typically obtained as salting-out constants, they can be used to find out how the interactions affect protein stability. The null point in the Hofmeister series, which divides protein denaturants from stabilizers, arises from opposite interactions with different classes of groups: Hofmeister ions salt out nonpolar groups and salt in the peptide group. Theories of how Hofmeister ion interactions work need to begin by explaining the mechanisms of these two classes of interactions. Salting-out nonpolar groups has been explained by the cavity model, but its use is controversial. When applied to model compound data, the cavity model 1) uses surface tension increments to predict the observed values of the salting-out constants, within a factor of 3, and 2) predicts that the salting-out constant should increase with the number of carbon atoms in the aliphatic side chain of an amino acid, as observed. The mechanism of interaction between Hofmeister ions and the peptide group is not well understood, and it is controversial whether this interaction is ion-specific, or whether it is nonspecific and the apparent specificity resides in interactions with nearby nonpolar groups. A nonspecific salting-in interaction is known to occur between simple ions and dipolar molecules; it depends on ionic strength, not on position in the Hofmeister series. A theory by Kirkwood predicts the strength of this interaction and indicates that it depends on the first power of the ionic strength. Ions interact with proteins in various ways besides the Hofmeister ion interactions discussed here, especially by charge interactions. Much of what is known about these interactions comes from studies by Serge Timasheff and his co-workers. A general model, suitable for analyzing diverse ion-protein interactions, is provided by the two-domain model of Record and co-workers.

journal_name

Biophys J

journal_title

Biophysical journal

authors

Baldwin RL

doi

10.1016/S0006-3495(96)79404-3

subject

Has Abstract

pub_date

1996-10-01 00:00:00

pages

2056-63

issue

eissn

0006-3495

issn

1542-0086

pii

S0006-3495(96)79404-3

journal_volume

pub_type

杂志文章

在线工具

How Hofmeister ion interactions affect protein stability.