Effects Of Hydrostatic Pressure On A Putative Piezophilic Homologue Of Staphylococcal Nuclease By Fluorescence And High-Pressure Nmr

Perturbation of proteins by high hydrostatic pressure facilitates observation of complex folding landscapes without the use of chemical denaturants or temperature, which often act globally rather than locally. This allows for more direct observation of folding intermediates and identification of foldons. The protein of interest in this study is a homologue of the well-characterized staphylococcal nuclease found in deep-sea bacterium Carnobacterium AT7. Due to the unusual nature of the nuclease, which is negatively charged on its surface but has the same active site conserved in nucleases, we were interested to see how its folding landscape differs from its mesophilic homologue. Kinetic and equilibrium parameters were observed using pressure-jump fluorescence. Surprisingly, our results revealed similar pressure effects on the mesophilic and piezophilic homologues.