Structure and flexibility of the thermophilic cold-shock protein of Thermus aquaticus.

Abstract

The thermophilic bacterium Thermus aquaticus is a well-known source of Taq polymerase. Here, we studied the structure and dynamics of the T. aquaticus cold-shock protein (Ta-Csp) to better understand its thermostability using NMR spectroscopy. We found that Ta-Csp has a five-stranded β-barrel structure with five salt bridges which are important for more rigid structure and a higher melting temperature (76 °C) of Ta-Csp compared to mesophilic and psychrophilic Csps. Microsecond to millisecond time scale exchange processes occur only at the β1-β2 surface region of the nucleic acid binding site with an average conformational exchange rate constant of 674 s(-1). The results imply that thermophilic Ta-Csp has a more rigid structure and may not need high structural flexibility to accommodate nucleic acids upon cold shock compared to its mesophile and psychrophile counterparts.

DOI: 10.1016/j.bbrc.2014.07.127

Cite this paper

@article{Jin2014StructureAF, title={Structure and flexibility of the thermophilic cold-shock protein of Thermus aquaticus.}, author={Bonghwan Jin and Ki-woong Jeong and Yangmee Kim}, journal={Biochemical and biophysical research communications}, year={2014}, volume={451 3}, pages={402-7} }