Revisiting the correlation between proteins' thermoresistance and organisms' thermophilicity

The possibility to rationally design protein mutants that remain structured and active at high temperatures strongly depends on a better understanding of the mechanisms of protein thermostability. Studies devoted to this issue often rely on the living temperature (Tenv) of the host organism rather than on the melting temperature (Tm) of the analyzed protein. To investigate the scale of this approximation, we probed the relationship between Tm and Tenv on a dataset of 127 proteins, and found a much weaker correlation than previously expected: the correlation coefficient is equal to 0.59 and the regression line is Tm ≈ 42.9°C + 0.62Tenv. To illustrate the effect of using Tenv rather than Tm to analyze protein thermoresistance, we derive statistical distance potentials, describing Glu-Arg and Asp-Arg salt bridges, from protein structure sets with high or low Tm or Tenv. The results show that the more favorable nature of salt bridges, relative to other interactions, at high temperatures is more clear-cut when defining thermoresistance in terms of Tm. The Tenv-based sets nevertheless remain informative. © The Author 2008. Published by Oxford University Press. All rights reserved.
Journal Article
Research Support, Non-U.S. Gov't
info:eu-repo/semantics/published