title: [A method of calculation of accessibility to solvent of aromatic amino acid residues of proteins in water-organic mixtures].
abstract: Suggested method for calculation of solvent accessibility of tryptophan and tyrosine residues in water-organic mixtures is based on evaluation of second order derivatives of UV spectra. Second order derivative of the spectrum enable differentiation between direct effects of the organic solvent on spectral characteristics of exposed aromatic amino acid residues and the effect of the organic solvent on protein conformation. The method is suitable for calculation of exposition of tryptophan in water-organic mixtures if the content of tyrosine amino acid residues in protein does not exceed the content of tryptophan. Similar method of calculation of exposition of tyrosine residues can be used in proteins when the content of tyrosine is at least 5-fold higher than the content of tryptophan. For example, solvent accessibility of tryptophan residues of chymotrypsin is calculated in the presence of various organic solvents including ethanol, dioxane, and dimethyl formamide.
authors.forename: A A
authors.initials: AA
authors.lastname: Shevchenko
authors.forename: O A
authors.initials: OA
authors.lastname: Kost
mesh_terms: D011506:Proteins / Q000737:chemistry*; D012995:Solubility; D012997:Solvents; D013056:Spectrophotometry, Ultraviolet; D014364:Tryptophan / Q000737:chemistry*; D014443:Tyrosine / Q000737:chemistry*
chemical_list: D011506:Proteins; D012997:Solvents; D014443:Tyrosine; D014364:Tryptophan
vernacular_title: Metod rascheta dostupnosti rastvoriteliu aromaticheskikh aminokislotnykh ostatkov belkov v vodno-organicheskikh smesiakh.