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. 1998 May;7(5):1201–1207. doi: 10.1002/pro.5560070515

What should the Z-score of native protein structures be?

L Zhang 1, J Skolnick 1
PMCID: PMC2144000  PMID: 9605325

Abstract

The Z-score of a protein is defined as the energy separation between the native fold and the average of an ensemble of misfolds in the units of the standard deviation of the ensemble. The Z-score is often used as a way of testing the knowledge-based potentials for their ability to recognize the native fold from other alternatives. However, it is not known what range of values the Z-scores should have if one had a correct potential. Here, we offer an estimate of Z-scores extracted from calorimetric measurements of proteins. The energies obtained from these experimental data are compared with those from computer simulations of a lattice model protein. It is suggested that the Z-scores calculated from different knowledge-based potentials are generally too small in comparison with the experimental values.

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Selected References

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