title: Communication: Accurate determination of side-chain torsion angle χ1 in proteins: phenylalanine residues.
abstract: Quantitative side-chain torsion angle χ(1) determinations of phenylalanine residues in Desulfovibrio vulgaris flavodoxin are carried out using exclusively the correlation between the experimental vicinal coupling constants and theoretically determined Karplus equations. Karplus coefficients for nine vicinal coupling related with the torsion angle χ(1) were calculated using the B3LYP functional and basis sets of different size. Optimized χ(1) angles are in outstanding agreement with those previously reported by employing x ray and NMR measurements.
authors.affiliation: Departamento de Química Física, Facultad de Química, Universidad de la Habana, La Habana 10400, Cuba.
authors.forename: R
authors.initials: R
authors.lastname: Suardíaz
authors.forename: R
authors.initials: R
authors.lastname: Crespo-Otero
authors.forename: C
authors.initials: C
authors.lastname: Pérez
authors.forename: J
authors.initials: J
authors.lastname: San Fabián
authors.forename: J M
authors.initials: JM
authors.lastname: García de la Vega
mesh_terms: D016969:Desulfovibrio vulgaris / Q000737:chemistry*; D005418:Flavodoxin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010649:Phenylalanine / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D005418:Flavodoxin; D010649:Phenylalanine