Corresponding state hypothesis along the GTPase cycle in homologues

Marina Katava et al. have tracked the effect of substrate binding on the conformational flexibilities of two homologous GTPase domains of different stability contents by mimicking the catalytic cycle. The notable finding is that for the hyperthermophilic specie only at its high working temperature the release of entropy in the domain upon the hydrolysis of the GTP molecule matches that of the mesophilic domain at ambient condition. This was probed following several functional modes of the protein considered important for signalling propagation upon reaction as well as for the allosteric activation. It was also confirmed that the key region ensuring the flexibility for the conformational change upon catalysis (the switch I region) is also the weakest part in the mesophilic domain, confirming a sort of stability/function trade-off. You can enjoy the paper here.