It is generally acknowledged that the mobility of protein atoms and the mobility of water molecules in the solvation layer are connected. In this article, we answer the question whether a similar interdependence exists between the motions of atoms of proteins separated by the hydration layers of variable thickness. The system consisted of a kinesin catalytic domain and a tubulin dimer. It was studied using molecular dynamics simulations. The analyzed atoms were located at the two distant protein surfaces that were facing each other. We demonstrated that the low-frequency (ca. 2 THz and less) collective movements of these two separate sets of atoms are to some extent interdependent. Based on this finding, it can be inferred that the low frequency large-scale internal motions of these proteins are also partially interdependent. The water-mediated protein–protein interactions, which are responsible for this interdependence, have a relatively long range of at least 2 nm at room temperature.