Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH
- Autores
- Vila, Jorge Alberto
- Año de publicación
- 2012
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- Tautomeric identification by direct observation of 15N chemical shifts of the imidazole ring of histidine (His) has become a common practice in NMR spectroscopy. However, such applications require knowledge of the "canonical"? limiting values of the 15N chemical shift of the imidazole ring of His in which each form of His, namely, the protonated (H+) and the tautomeric Nε2 - H and N δ1 - H forms, respectively, is present to the extent of 100%. So far, the adopted canonical limiting values of the 15N chemical shift have been those available from model compounds. Whether these canonical values reflect those of the individual pure forms of His is investigated here by carrying out an analysis of the second-order shielding differences, ΔΔ = |Δε - Δδ |, with Δζ (ζ = ε or δ) being the density functional theory (DFT)-computed average shielding differences between the two nitrogens of the imidazole ring of His in each pure tautomeric form. In the high-pH limit, the results indicate that (i) the ΔΔ values from the DFT-computed shielding, but not from the commonly used canonical limiting values, are in closer agreement with those obtained with experimental chemical shift data from model compounds in solution and solid-state NMR; and (ii) the commonly used canonical limiting values of the 15N chemical shifts lead to an average tautomeric equilibrium constant that differs by a factor of ∼2.6 from the one computed by using DFT-based 15N limiting values, raising concern about the practice of using canonical limiting 15N values. This can be avoided by reporting tautomeric equilibrium constants computed by using only limiting 15N values for the N ε2 - H tautomer.
Fil: Vila, Jorge Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina - Materia
-
SHIELDING
15N
VALIDATION
LIMITING VALUES - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
- Repositorio
- Institución
- Consejo Nacional de Investigaciones Científicas y Técnicas
- OAI Identificador
- oai:ri.conicet.gov.ar:11336/184758
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Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pHVila, Jorge AlbertoSHIELDING15NVALIDATIONLIMITING VALUEShttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1Tautomeric identification by direct observation of 15N chemical shifts of the imidazole ring of histidine (His) has become a common practice in NMR spectroscopy. However, such applications require knowledge of the "canonical"? limiting values of the 15N chemical shift of the imidazole ring of His in which each form of His, namely, the protonated (H+) and the tautomeric Nε2 - H and N δ1 - H forms, respectively, is present to the extent of 100%. So far, the adopted canonical limiting values of the 15N chemical shift have been those available from model compounds. Whether these canonical values reflect those of the individual pure forms of His is investigated here by carrying out an analysis of the second-order shielding differences, ΔΔ = |Δε - Δδ |, with Δζ (ζ = ε or δ) being the density functional theory (DFT)-computed average shielding differences between the two nitrogens of the imidazole ring of His in each pure tautomeric form. In the high-pH limit, the results indicate that (i) the ΔΔ values from the DFT-computed shielding, but not from the commonly used canonical limiting values, are in closer agreement with those obtained with experimental chemical shift data from model compounds in solution and solid-state NMR; and (ii) the commonly used canonical limiting values of the 15N chemical shifts lead to an average tautomeric equilibrium constant that differs by a factor of ∼2.6 from the one computed by using DFT-based 15N limiting values, raising concern about the practice of using canonical limiting 15N values. This can be avoided by reporting tautomeric equilibrium constants computed by using only limiting 15N values for the N ε2 - H tautomer.Fil: Vila, Jorge Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; ArgentinaAmerican Chemical Society2012-10info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/184758Vila, Jorge Alberto; Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH; American Chemical Society; Journal of Physical Chemistry B; 116; 23; 10-2012; 6665-66691520-6106CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1021/jp211196rinfo:eu-repo/semantics/altIdentifier/url/https://pubs.acs.org/doi/10.1021/jp211196rinfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:20:41Zoai:ri.conicet.gov.ar:11336/184758instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 10:20:41.52CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse |
dc.title.none.fl_str_mv |
Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH |
title |
Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH |
spellingShingle |
Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH Vila, Jorge Alberto SHIELDING 15N VALIDATION LIMITING VALUES |
title_short |
Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH |
title_full |
Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH |
title_fullStr |
Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH |
title_full_unstemmed |
Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH |
title_sort |
Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH |
dc.creator.none.fl_str_mv |
Vila, Jorge Alberto |
author |
Vila, Jorge Alberto |
author_facet |
Vila, Jorge Alberto |
author_role |
author |
dc.subject.none.fl_str_mv |
SHIELDING 15N VALIDATION LIMITING VALUES |
topic |
SHIELDING 15N VALIDATION LIMITING VALUES |
purl_subject.fl_str_mv |
https://purl.org/becyt/ford/1.3 https://purl.org/becyt/ford/1 |
dc.description.none.fl_txt_mv |
Tautomeric identification by direct observation of 15N chemical shifts of the imidazole ring of histidine (His) has become a common practice in NMR spectroscopy. However, such applications require knowledge of the "canonical"? limiting values of the 15N chemical shift of the imidazole ring of His in which each form of His, namely, the protonated (H+) and the tautomeric Nε2 - H and N δ1 - H forms, respectively, is present to the extent of 100%. So far, the adopted canonical limiting values of the 15N chemical shift have been those available from model compounds. Whether these canonical values reflect those of the individual pure forms of His is investigated here by carrying out an analysis of the second-order shielding differences, ΔΔ = |Δε - Δδ |, with Δζ (ζ = ε or δ) being the density functional theory (DFT)-computed average shielding differences between the two nitrogens of the imidazole ring of His in each pure tautomeric form. In the high-pH limit, the results indicate that (i) the ΔΔ values from the DFT-computed shielding, but not from the commonly used canonical limiting values, are in closer agreement with those obtained with experimental chemical shift data from model compounds in solution and solid-state NMR; and (ii) the commonly used canonical limiting values of the 15N chemical shifts lead to an average tautomeric equilibrium constant that differs by a factor of ∼2.6 from the one computed by using DFT-based 15N limiting values, raising concern about the practice of using canonical limiting 15N values. This can be avoided by reporting tautomeric equilibrium constants computed by using only limiting 15N values for the N ε2 - H tautomer. Fil: Vila, Jorge Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina |
description |
Tautomeric identification by direct observation of 15N chemical shifts of the imidazole ring of histidine (His) has become a common practice in NMR spectroscopy. However, such applications require knowledge of the "canonical"? limiting values of the 15N chemical shift of the imidazole ring of His in which each form of His, namely, the protonated (H+) and the tautomeric Nε2 - H and N δ1 - H forms, respectively, is present to the extent of 100%. So far, the adopted canonical limiting values of the 15N chemical shift have been those available from model compounds. Whether these canonical values reflect those of the individual pure forms of His is investigated here by carrying out an analysis of the second-order shielding differences, ΔΔ = |Δε - Δδ |, with Δζ (ζ = ε or δ) being the density functional theory (DFT)-computed average shielding differences between the two nitrogens of the imidazole ring of His in each pure tautomeric form. In the high-pH limit, the results indicate that (i) the ΔΔ values from the DFT-computed shielding, but not from the commonly used canonical limiting values, are in closer agreement with those obtained with experimental chemical shift data from model compounds in solution and solid-state NMR; and (ii) the commonly used canonical limiting values of the 15N chemical shifts lead to an average tautomeric equilibrium constant that differs by a factor of ∼2.6 from the one computed by using DFT-based 15N limiting values, raising concern about the practice of using canonical limiting 15N values. This can be avoided by reporting tautomeric equilibrium constants computed by using only limiting 15N values for the N ε2 - H tautomer. |
publishDate |
2012 |
dc.date.none.fl_str_mv |
2012-10 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://hdl.handle.net/11336/184758 Vila, Jorge Alberto; Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH; American Chemical Society; Journal of Physical Chemistry B; 116; 23; 10-2012; 6665-6669 1520-6106 CONICET Digital CONICET |
url |
http://hdl.handle.net/11336/184758 |
identifier_str_mv |
Vila, Jorge Alberto; Limiting values of the 15N chemical shift of the imidazole ring of histidine at high pH; American Chemical Society; Journal of Physical Chemistry B; 116; 23; 10-2012; 6665-6669 1520-6106 CONICET Digital CONICET |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/doi/10.1021/jp211196r info:eu-repo/semantics/altIdentifier/url/https://pubs.acs.org/doi/10.1021/jp211196r |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
dc.format.none.fl_str_mv |
application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
American Chemical Society |
publisher.none.fl_str_mv |
American Chemical Society |
dc.source.none.fl_str_mv |
reponame:CONICET Digital (CONICET) instname:Consejo Nacional de Investigaciones Científicas y Técnicas |
reponame_str |
CONICET Digital (CONICET) |
collection |
CONICET Digital (CONICET) |
instname_str |
Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.name.fl_str_mv |
CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.mail.fl_str_mv |
dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar |
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1844614189186809856 |
score |
13.070432 |