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Title: Innovative scattering analysis shows that hydrophobic disordered proteins are expanded in water

Abstract

A substantial fraction of the proteome is intrinsically disordered, and even well-folded proteins adopt non-native geometries during synthesis, folding, transport, and turnover. Characterization of intrinsically disordered proteins (IDPs) is challenging, in part because of a lack of accurate physical models and the difficulty of interpreting experimental results. We have developed a general method to extract the dimensions and solvent quality (self-interactions) of IDPs from a single small-angle x-ray scattering measurement. We applied this procedure to a variety of IDPs and found that even IDPs with low net charge and high hydrophobicity remain highly expanded in water, contrary to the general expectation that protein-like sequences collapse in water. Our results suggest that the unfolded state of most foldable sequences is expanded; we conjecture that this property was selected by evolution to minimize misfolding and aggregation.


Citation Formats

Riback, Joshua A., Bowman, Micayla A., Zmyslowski, Adam M., Knoverek, Catherine R., Jumper, John M., Hinshaw, James R., Kaye, Emily B., Freed, Karl F., Clark, Patricia L., and Sosnick, Tobin R.. Innovative scattering analysis shows that hydrophobic disordered proteins are expanded in water. United States: N. p., 2017. Web. doi:10.1126/science.aan5774.
Riback, Joshua A., Bowman, Micayla A., Zmyslowski, Adam M., Knoverek, Catherine R., Jumper, John M., Hinshaw, James R., Kaye, Emily B., Freed, Karl F., Clark, Patricia L., & Sosnick, Tobin R.. Innovative scattering analysis shows that hydrophobic disordered proteins are expanded in water. United States. doi:10.1126/science.aan5774.
Riback, Joshua A., Bowman, Micayla A., Zmyslowski, Adam M., Knoverek, Catherine R., Jumper, John M., Hinshaw, James R., Kaye, Emily B., Freed, Karl F., Clark, Patricia L., and Sosnick, Tobin R.. 2017. "Innovative scattering analysis shows that hydrophobic disordered proteins are expanded in water". United States. doi:10.1126/science.aan5774.
@article{osti_1400299,
title = {Innovative scattering analysis shows that hydrophobic disordered proteins are expanded in water},
author = {Riback, Joshua A. and Bowman, Micayla A. and Zmyslowski, Adam M. and Knoverek, Catherine R. and Jumper, John M. and Hinshaw, James R. and Kaye, Emily B. and Freed, Karl F. and Clark, Patricia L. and Sosnick, Tobin R.},
abstractNote = {A substantial fraction of the proteome is intrinsically disordered, and even well-folded proteins adopt non-native geometries during synthesis, folding, transport, and turnover. Characterization of intrinsically disordered proteins (IDPs) is challenging, in part because of a lack of accurate physical models and the difficulty of interpreting experimental results. We have developed a general method to extract the dimensions and solvent quality (self-interactions) of IDPs from a single small-angle x-ray scattering measurement. We applied this procedure to a variety of IDPs and found that even IDPs with low net charge and high hydrophobicity remain highly expanded in water, contrary to the general expectation that protein-like sequences collapse in water. Our results suggest that the unfolded state of most foldable sequences is expanded; we conjecture that this property was selected by evolution to minimize misfolding and aggregation.},
doi = {10.1126/science.aan5774},
journal = {Science},
number = 6360,
volume = 358,
place = {United States},
year = 2017,
month =
}
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