A full conformational space analysis of bilirubin

Ab initio methods were utilized in a gas-phase systematic conformational search of bilirubin conformers. The whole molecule was divided into four fragments. Most stable conformers of them were employed to build 196 conformers of the complete bilirubin molecule. Initial geometries were optimized usin...

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Detalles Bibliográficos
Autores: Vega Hissi, Esteban Gabriel, Garro Martinez, Juan Ceferino, Zamarbide, Graciela Nidia, Estrada, Mario Rinaldo, Knak Jensen, Svend J., Tomas Vert, Francisco, Csizmadia, Imre G.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/158403
Acceso en línea:http://hdl.handle.net/11336/158403
Access Level:acceso abierto
Palabra clave:BILIRRUBIN
RIDGE-TILE
HYDROGEN BOND PATTERN
FLEXIBILITY
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descripción
Sumario:Ab initio methods were utilized in a gas-phase systematic conformational search of bilirubin conformers. The whole molecule was divided into four fragments. Most stable conformers of them were employed to build 196 conformers of the complete bilirubin molecule. Initial geometries were optimized using HF/321Glevel of theory and the minimum energy conformerswere then reoptimized at B3LYP/6-31G(d) level. Ridge-tile conformer was the most stable one, in perfect agreement with X-ray data. We found that while tetrapyrrole backbone shows some flexibility, propionic acid side chains have a greater influence in bilirubin conformation because they can interact through different hydrogen bond patterns with the backbone and between them.