Olga Ivchenko1, 2, Petra Imhof3, Moritz Zaiss4, Peter Bachert4
1Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; 2Molecular Biophysics, Interdisciplinary Center for Scientific Computing (IWR), Heidelberg, Germany; 3Molecular Biophysics , Interdisciplinary Center for Scientific Computing (IWR), Heidelberg, Germany; 4Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
The chemical exchange rate was determined for creatine NH2 group (kex =102.9 s-1) at the pH=6.5 using quantum mechanics/molecular mechanics simulations (QM/MM) in combination with umbrella sampling simulations. This value is in agreement with the value from CEST experiment. The chemical exchange rate was determining using Arrhenius equation: