Finally, the protocol was tested on a fragment of unknown allosteric effect. Fragment binder 4[37] was processed using a similar distance restraint scheme as for 3u. The resulting active conformation probability distribution for 4 is broad and does not suggest allosteric inhibition when compared with the reference system (Figure ). The major binding pose of 4 also corresponds to a "sideway" binding mode that engage in hydrogen bonds with E200, (Figure ) on the α3 helix and adjacent to the binding