Abstact

How does the structure of a protein change as the temperature is raised from cryogenic conditions at 100 K to 393 K? Understanding the structure and dynamics of proteins under environmental extremes is relevant for human health, biotechnological applications, and our search for life elsewhere in the universe. Here we reveal the high temperature crystal structure of a hyperthermophilic (Pyrococcus furiosus) rubredoxin at 393 K (120 degrees C), together with multiple complementary structures down to 100 K. The results are compared with molecular dynamics calculations. Significant changes in H-bonding are observed. Discussions about high-temperature protein structure and stability need to recognize that low temperature structures may not represent the high temperature case.