Different predicted hydrogen atom positions. Prediction of the hydrogen position of Thr118 by three Different programs in PDB structure 1muw. The structure is part of the Buried test set. Amino acids from left to right: Ala114, Thr118, Thr90, Thr133, Asn121. Protoss and Protonate3D orientate the hydrogen correctly, while X-PLOR is off by about an Angstrom.