期刊
BIOPHYSICAL CHEMISTRY
卷 159, 期 1, 页码 48-57出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.bpc.2011.05.005
关键词
EcoSSB; ssDNA binding; ITC; Opposite heat capacity effect; Salt dependence; SSB-ssDNA thermodynamics
资金
- NIH [GM30498]
We have previously shown that formation of a 1:1 fully wrapped complex of Escherichia coli SSB tetramer with (dT)(70) displays a temperature-dependent sign reversal of the binding heat capacity (Delta C-P). Here we examine SSB binding to shorter oligodeoxynucleotides ((dX)(35)) to probe whether this effect requires binding of one or two (dX)(35) molecules per SSB tetramer. We find that the Delta C-P for the first molecule of (dX)(35) is always negative. However, a sign reversal of Delta C-P from negative to positive occurs with increasing temperature for binding of the second (dX)(35). This striking behavior of Delta C-P for the second (dX)(35) appears linked to conformational changes within the ssDNA-SSB complex that are required to form a fully wrapped (SSB)(65) binding mode. These results also underscore that binding heat capacities of macromolecular interactions have multiple origins that cannot be understood simply on the basis of examining static structures. (C) 2011 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据