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Approximates the Boltzmann probability for the occurrence of a rotamer. The method, usage examples, and analysis scripts are published in Fleishman et al. (2011) Protein Sci. 20:753.
Residues to be tested are defined using a task_factory (set all inert residues to no repack). A first-pass alanine scan looks at which residues contribute substantially to binding affinity. Then, the rotamer set for each of these residues is taken, each rotamer is imposed on the pose, the surrounding shell is repacked and minimized and the energy is summed to produce a Boltzmann probability. Can be computed in both the bound and unbound state.
This is apparently a good discriminator between designs and natives, with many designs showing high probabilities for their highly contributing rotamers in both the bound and unbound states.
The filter also reports a modified value for the complex ddG. It computes the starting ddG and then reduces from this energy a fraction of the interaction energy of each residue the rotamer probability of which is below a certain threshold. The interaction energy is computed only for the residue under study and its contacts with residues on another chain.
For real-valued contexts, the value of the filter by default is the modified ddG value. If the no_modified_ddG option is set true, then the value of the filter is equal to the negative of the average rotamer probablility across the evaluated residues.
Works with symmetric poses and poses with symmetric "building blocks".
<RotamerBoltzmannWeight name="(&string)" task_operations="(comma-delimited list)" radius="(6.0 &Real)" jump="(1 &Integer)" sym_dof_names="('' &string)" unbound="(1 &bool)" ddG_threshold="(1.5 &Real)" scorefxn="(score12 &string)" temperature="(0.8 &Real)" energy_reduction_factor="(0.5 &Real)" repack="(1&bool)" skip_ala_scan="(0 &bool)" skip_report="(0 &bool)" no_modified_ddG="(0 &bool)">
<Threshold restype="???" threshold_probability="(&Real)"/>
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</RotamerBoltzmannWeight>