Structure and Dynamics of a Compact State of a Multidomain Protein, the Mercuric Ion Reductase

Summary, in English

The functional efficacy of colocalized, linked protein domains is dependent on linker flexibility and system compaction. However, the detailed characterization of these properties in aqueous solution presents an enduring challenge. Here, we employ a novel, to our knowledge, combination of complementary techniques, including small-angle neutron scattering, neutron spin-echo spectroscopy, and all-atom molecular dynamics and coarse-grained simulation, to identify and characterize in detail the structure and dynamics of a compact form of mercuric ion reductase (MerA), an enzyme central to bacterial mercury resistance. MerA possesses metallochaperone-like N-terminal domains (NmerA) tethered to its catalytic core domain by linkers. The NmerA domains are found to interact principally through electrostatic interactions with the core, leashed by the linkers so as to subdiffuse on the surface over an area close to the core C-terminal Hg(II)-binding cysteines. How this compact, dynamical arrangement may facilitate delivery of Hg(II) from NmerA to the core domain is discussed.

• Author: Liang Hong; Melissa Sharp; Simon Poblete; Ralf Bieh; Michaele Zamponi; Noemi Szekely; Marie-Sousai Appavou; Roland G. Winkler; Rachel E. Nauss; Alexander Johs; Jerry M. Parks; Zheng Yi; Xiaolin Cheng; Liyuan Liang; Michael Ohl; Susan M. Miller; Dieter Richter; Gerhard Gompper; Jeremy C. Smith
• Department/s: European Spallation Source ESS AB
• Publishing year: 2014
• Language: English
• Pages: 393-400
• Publication/Series: Biophysical Journal
• Volume: 107
• Issue: 2
• Links: http://dx.doi.org/10.1016/j.bpj.2014.06.013
• Document type: Journal article
• Publisher: Cell Press
• Topic: Biophysics
• Status: Published
• ISBN/ISSN/Other: ISSN: 1542-0086