Cargando…
A GAP‐GTPase‐GDP‐P(i) Intermediate Crystal Structure Analyzed by DFT Shows GTP Hydrolysis Involves Serial Proton Transfers
Cell signaling by small G proteins uses an ON to OFF signal based on conformational changes following the hydrolysis of GTP to GDP and release of dihydrogen phosphate (P(i)). The catalytic mechanism of GTP hydrolysis by RhoA is strongly accelerated by a GAP protein and is now well defined, but timin...
Autores principales: | , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
John Wiley and Sons Inc.
2019
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6771576/ https://www.ncbi.nlm.nih.gov/pubmed/31038818 http://dx.doi.org/10.1002/chem.201901627 |
_version_ | 1783455717743656960 |
---|---|
author | Molt, Robert W. Pellegrini, Erika Jin, Yi |
author_facet | Molt, Robert W. Pellegrini, Erika Jin, Yi |
author_sort | Molt, Robert W. |
collection | PubMed |
description | Cell signaling by small G proteins uses an ON to OFF signal based on conformational changes following the hydrolysis of GTP to GDP and release of dihydrogen phosphate (P(i)). The catalytic mechanism of GTP hydrolysis by RhoA is strongly accelerated by a GAP protein and is now well defined, but timing of inorganic phosphate release and signal change remains unresolved. We have generated a quaternary complex for RhoA‐GAP‐GDP‐P(i). Its 1.75 Å crystal structure shows geometry for ionic and hydrogen bond coordination of GDP and P(i) in an intermediate state. It enables the selection of a QM core for DFT exploration of a 20 H‐bonded network. This identifies serial locations of the two mobile protons from the original nucleophilic water molecule, showing how they move in three rational steps to form a stable quaternary complex. It also suggests how two additional proton transfer steps can facilitate P(i) release. |
format | Online Article Text |
id | pubmed-6771576 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | John Wiley and Sons Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-67715762019-10-03 A GAP‐GTPase‐GDP‐P(i) Intermediate Crystal Structure Analyzed by DFT Shows GTP Hydrolysis Involves Serial Proton Transfers Molt, Robert W. Pellegrini, Erika Jin, Yi Chemistry Communications Cell signaling by small G proteins uses an ON to OFF signal based on conformational changes following the hydrolysis of GTP to GDP and release of dihydrogen phosphate (P(i)). The catalytic mechanism of GTP hydrolysis by RhoA is strongly accelerated by a GAP protein and is now well defined, but timing of inorganic phosphate release and signal change remains unresolved. We have generated a quaternary complex for RhoA‐GAP‐GDP‐P(i). Its 1.75 Å crystal structure shows geometry for ionic and hydrogen bond coordination of GDP and P(i) in an intermediate state. It enables the selection of a QM core for DFT exploration of a 20 H‐bonded network. This identifies serial locations of the two mobile protons from the original nucleophilic water molecule, showing how they move in three rational steps to form a stable quaternary complex. It also suggests how two additional proton transfer steps can facilitate P(i) release. John Wiley and Sons Inc. 2019-05-27 2019-06-26 /pmc/articles/PMC6771576/ /pubmed/31038818 http://dx.doi.org/10.1002/chem.201901627 Text en © 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Communications Molt, Robert W. Pellegrini, Erika Jin, Yi A GAP‐GTPase‐GDP‐P(i) Intermediate Crystal Structure Analyzed by DFT Shows GTP Hydrolysis Involves Serial Proton Transfers |
title | A GAP‐GTPase‐GDP‐P(i) Intermediate Crystal Structure Analyzed by DFT Shows GTP Hydrolysis Involves Serial Proton Transfers |
title_full | A GAP‐GTPase‐GDP‐P(i) Intermediate Crystal Structure Analyzed by DFT Shows GTP Hydrolysis Involves Serial Proton Transfers |
title_fullStr | A GAP‐GTPase‐GDP‐P(i) Intermediate Crystal Structure Analyzed by DFT Shows GTP Hydrolysis Involves Serial Proton Transfers |
title_full_unstemmed | A GAP‐GTPase‐GDP‐P(i) Intermediate Crystal Structure Analyzed by DFT Shows GTP Hydrolysis Involves Serial Proton Transfers |
title_short | A GAP‐GTPase‐GDP‐P(i) Intermediate Crystal Structure Analyzed by DFT Shows GTP Hydrolysis Involves Serial Proton Transfers |
title_sort | gap‐gtpase‐gdp‐p(i) intermediate crystal structure analyzed by dft shows gtp hydrolysis involves serial proton transfers |
topic | Communications |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6771576/ https://www.ncbi.nlm.nih.gov/pubmed/31038818 http://dx.doi.org/10.1002/chem.201901627 |
work_keys_str_mv | AT moltrobertw agapgtpasegdppiintermediatecrystalstructureanalyzedbydftshowsgtphydrolysisinvolvesserialprotontransfers AT pellegrinierika agapgtpasegdppiintermediatecrystalstructureanalyzedbydftshowsgtphydrolysisinvolvesserialprotontransfers AT jinyi agapgtpasegdppiintermediatecrystalstructureanalyzedbydftshowsgtphydrolysisinvolvesserialprotontransfers AT moltrobertw gapgtpasegdppiintermediatecrystalstructureanalyzedbydftshowsgtphydrolysisinvolvesserialprotontransfers AT pellegrinierika gapgtpasegdppiintermediatecrystalstructureanalyzedbydftshowsgtphydrolysisinvolvesserialprotontransfers AT jinyi gapgtpasegdppiintermediatecrystalstructureanalyzedbydftshowsgtphydrolysisinvolvesserialprotontransfers |