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Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase

An extremely low-field signal (at approximately 18 p.p.m.) in the (1)H NMR spectrum of rhamnogalacturonan acetylesterase (RGAE) shows the presence of a short strong hydrogen bond in the structure. This signal was also present in the mutant RGAE D192N, in which Asp192, which is part of the catalytic...

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Autores principales: Langkilde, Annette, Kristensen, Søren M., Lo Leggio, Leila, Mølgaard, Anne, Jensen, Jan H., Houk, Andrew R., Navarro Poulsen, Jens-Christian, Kauppinen, Sakari, Larsen, Sine
Formato: Texto
Lenguaje:English
Publicado: International Union of Crystallography 2008
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2483496/
https://www.ncbi.nlm.nih.gov/pubmed/18645234
http://dx.doi.org/10.1107/S0907444908017083
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author Langkilde, Annette
Kristensen, Søren M.
Lo Leggio, Leila
Mølgaard, Anne
Jensen, Jan H.
Houk, Andrew R.
Navarro Poulsen, Jens-Christian
Kauppinen, Sakari
Larsen, Sine
author_facet Langkilde, Annette
Kristensen, Søren M.
Lo Leggio, Leila
Mølgaard, Anne
Jensen, Jan H.
Houk, Andrew R.
Navarro Poulsen, Jens-Christian
Kauppinen, Sakari
Larsen, Sine
author_sort Langkilde, Annette
collection PubMed
description An extremely low-field signal (at approximately 18 p.p.m.) in the (1)H NMR spectrum of rhamnogalacturonan acetylesterase (RGAE) shows the presence of a short strong hydrogen bond in the structure. This signal was also present in the mutant RGAE D192N, in which Asp192, which is part of the catalytic triad, has been replaced with Asn. A careful analysis of wild-type RGAE and RGAE D192N was conducted with the purpose of identifying possible candidates for the short hydrogen bond with the 18 p.p.m. deshielded proton. Theor­etical calculations of chemical shift values were used in the interpretation of the experimental (1)H NMR spectra. The crystal structure of RGAE D192N was determined to 1.33 Å resolution and refined to an R value of 11.6% for all data. The structure is virtually identical to the high-resolution (1.12 Å) structure of the wild-type enzyme except for the interactions involving the mutation and a disordered loop. Searches of the Cambridge Structural Database were conducted to obtain information on the donor–acceptor distances of different types of hydrogen bonds. The short hydrogen-bond inter­actions found in RGAE have equivalents in small-molecule structures. An examination of the short hydrogen bonds in RGAE, the calculated pK (a) values and solvent-accessibilities identified a buried carboxylic acid carboxylate hydrogen bond between Asp75 and Asp87 as the likely origin of the 18 p.p.m. signal. Similar hydrogen-bond interactions between two Asp or Glu carboxy groups were found in 16% of a homology-reduced set of high-quality structures extracted from the PDB. The shortest hydrogen bonds in RGAE are all located close to the active site and short interactions between Ser and Thr side-chain OH groups and backbone carbonyl O atoms seem to play an important role in the stability of the protein structure. These results illustrate the significance of short strong hydrogen bonds in proteins.
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spelling pubmed-24834962009-03-05 Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase Langkilde, Annette Kristensen, Søren M. Lo Leggio, Leila Mølgaard, Anne Jensen, Jan H. Houk, Andrew R. Navarro Poulsen, Jens-Christian Kauppinen, Sakari Larsen, Sine Acta Crystallogr D Biol Crystallogr Research Papers An extremely low-field signal (at approximately 18 p.p.m.) in the (1)H NMR spectrum of rhamnogalacturonan acetylesterase (RGAE) shows the presence of a short strong hydrogen bond in the structure. This signal was also present in the mutant RGAE D192N, in which Asp192, which is part of the catalytic triad, has been replaced with Asn. A careful analysis of wild-type RGAE and RGAE D192N was conducted with the purpose of identifying possible candidates for the short hydrogen bond with the 18 p.p.m. deshielded proton. Theor­etical calculations of chemical shift values were used in the interpretation of the experimental (1)H NMR spectra. The crystal structure of RGAE D192N was determined to 1.33 Å resolution and refined to an R value of 11.6% for all data. The structure is virtually identical to the high-resolution (1.12 Å) structure of the wild-type enzyme except for the interactions involving the mutation and a disordered loop. Searches of the Cambridge Structural Database were conducted to obtain information on the donor–acceptor distances of different types of hydrogen bonds. The short hydrogen-bond inter­actions found in RGAE have equivalents in small-molecule structures. An examination of the short hydrogen bonds in RGAE, the calculated pK (a) values and solvent-accessibilities identified a buried carboxylic acid carboxylate hydrogen bond between Asp75 and Asp87 as the likely origin of the 18 p.p.m. signal. Similar hydrogen-bond interactions between two Asp or Glu carboxy groups were found in 16% of a homology-reduced set of high-quality structures extracted from the PDB. The shortest hydrogen bonds in RGAE are all located close to the active site and short interactions between Ser and Thr side-chain OH groups and backbone carbonyl O atoms seem to play an important role in the stability of the protein structure. These results illustrate the significance of short strong hydrogen bonds in proteins. International Union of Crystallography 2008-08-01 2008-07-17 /pmc/articles/PMC2483496/ /pubmed/18645234 http://dx.doi.org/10.1107/S0907444908017083 Text en © Langkilde et al. 2008 http://creativecommons.org/licenses/by/2.0/uk/ This is an open-access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
spellingShingle Research Papers
Langkilde, Annette
Kristensen, Søren M.
Lo Leggio, Leila
Mølgaard, Anne
Jensen, Jan H.
Houk, Andrew R.
Navarro Poulsen, Jens-Christian
Kauppinen, Sakari
Larsen, Sine
Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase
title Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase
title_full Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase
title_fullStr Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase
title_full_unstemmed Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase
title_short Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase
title_sort short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase
topic Research Papers
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2483496/
https://www.ncbi.nlm.nih.gov/pubmed/18645234
http://dx.doi.org/10.1107/S0907444908017083
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