利用氙对来自肉葡萄球菌的HPr的I14A突变体中一个工程化腔进行核磁共振光谱测绘。

NMR-spectroscopic mapping of an engineered cavity in the I14A mutant of HPr from Staphylococcus carnosus using xenon.

作者信息

Gröger Christian, Möglich Andreas, Pons Miguel, Koch Brigitte, Hengstenberg Wolfgang, Kalbitzer Hans Robert, Brunner Eike

机构信息

Institute of Biophysics and Physical Biochemistry, University of Regensburg, D-93040, Regensburg, Germany.

出版信息

J Am Chem Soc. 2003 Jul 23;125(29):8726-7. doi: 10.1021/ja030113t.

DOI:10.1021/ja030113t

PMID:12862458

Abstract

The interaction between the histidine-containing phosphocarrier protein HPr and xenon atoms in solution is studied in the present paper. Wild-type HPr as well as the exchange mutant I14A have been studied. Specific binding of xenon into an engineered cavity created via the exchange of amino acid residue I14 by alanine could be shown using 1H-15N heteronuclear single-quantum coherence (HSQC) spectroscopy. Xenon binding results in pronounced changes of the 1H and 15N chemical shifts of amide groups close to the cavity. In addition to this observation which allows the NMR-spectroscopic mapping of such cavities, we have shown that the entire molecule is slightly rearranged as a result of xenon binding. In contrast, wild-type HPr only exhibits minor chemical shift changes due to the nonspecific interactions with the xenon atoms in solution.

摘要

本文研究了含组氨酸的磷酸载体蛋白HPr与溶液中氙原子之间的相互作用。研究了野生型HPr以及交换突变体I14A。通过使用1H-15N异核单量子相干（HSQC）光谱，可以证明氙特异性结合到通过将氨基酸残基I14替换为丙氨酸而产生的工程化腔中。氙的结合导致靠近腔的酰胺基团的1H和15N化学位移发生明显变化。除了这一允许对这种腔进行NMR光谱测绘的观察结果外，我们还表明，由于氙的结合，整个分子略有重排。相比之下，野生型HPr仅由于与溶液中氙原子的非特异性相互作用而表现出微小的化学位移变化。