Our previous INS studies of ¿dry¿/hydrated apoferritin show that the hydrated protein undergoes a dynamical transition, Td, at 200K. Such behavior, first modeled by Doster et al (Nature, 1989), is attributed to Debye-like vibrations below, and quasi-harmonic behavior above, Td. Analysis of mean squared displacement data, however, shows that in apoferritin both ¿dry¿ and hydrated materials actually deviate from harmonic behavior at 100K; possibly a consequence of amino acid methyl group rotations. We now wish to study further the onset of methyl group activity using a series of proteins with different conformations (helices vs. beta sheets) and methyl group constituents Understanding the origin of this 100K inflexion will allow us to review the original formalization of Doster et al. In addition, the results from this study will be used to assist subsequent molecular dynamic simulations.