Before revision: Molecular dynamics (MD) simulations using a graphics processing unit (GPU) has been employed in order to determine the conformational space of the methane-thiosulfonate spin label (MTSL) attached to the activation loop of the Aurora-A kinase protein and compared with quantum mechanical (QM) methods rooted on density functional theory (DFT). MD provided a wealth of information about interactions between the MTSL and the residues of the protein and  on the different motional contributions to the overall dynamics of the MTSL . Data obtained from MD were seen to be in good agreement with those obtained from QM but the dynamics of the system revealed more interactions than those observed from QMmethods .
After revision: Molecular dynamics (MD) simulations using a graphics processing unit (GPU) has been employed in order to determine the conformational space of the methane-thiosulfonate spin label (MTSL) attached to the activation loop of the Aurora-A kinase activation loop in a very short time and with good quality of the sampling. The MD simulation provided a wealth of information about interactions between the MTSL and the residues of the protein and on the different motional contributions to the overall dynamics of the MTSL . Data obtained from MD were seen to be in good agreement with those obtained from QM but the dynamics of the system revealed more interactions than those observed from QMmethods .