[Influence of dioxane on the hydration shell of polypeptides].

[Influence of dioxane on the hydration shell of polypeptides].

Bioorganicheskaia khimiia (2012-09-25)

O N Makshakova, D A Faĭzullin, Iu F Zuev

ABSTRACT

Our interest in modifying influence of the low-molecular organic compounds on the hydration shell of biopolymers is due to a well-known fact that the former can act as regulators of the enzymatic activity changed the hydration shell of the latter. Dioxane was chosen because of its wide application in non-aqueous biocatalysis. In the present study we investigate the mechanisms of the dioxane influence on water of the first hydration layer of the model polypeptides by FTIR-spectroscopy during simultaneous sorption of water-dioxane vapors into the polypeptide films at low water activity. It was found that modification of the hydration shell of the studied polypeptides was mainly due to the indirect ordering ofpolypeptide secondary structure at penetration of dioxane molecules at these conditions.

MATERIALS

Product Number

Brand

Product Description

676934

Sigma-Aldrich

1,4-Dioxane, ACS reagent, ≥99.0%

360481

Sigma-Aldrich

1,4-Dioxane, ACS reagent, ≥99.0%, contains ≤25 ppm BHT as stabilizer

34857

Sigma-Aldrich

1,4-Dioxane, suitable for HPLC, ≥99.5%

631833

Supelco

1,4-Dioxane solution, NMR reference standard, 5 mM in benzene-d₆ (99.6 atom % D), NMR tube size 3 mm × 8 in.

684228

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D), NMR tube size 10 mm × 8 in.

704814

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 10 mM in D₂O ("100%", 99.96 atom % D), NMR tube size 5 mm × 7 in.

736171

Supelco

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D), NMR tube size 5 mm × 8 in.

631868

Supelco

1,4-Dioxane solution, NMR reference standard, 5 mM in chloroform-d (99.8 atom % D), NMR tube size 3 mm × 8 in.

76887

Supelco

1,4-Dioxane, analytical standard

551368

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D)

612073

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D), chromium(III) acetylacetonate 5 mg/mL, NMR tube size 3 mm × 8 in.

611905

Sigma-Aldrich

1,4-Dioxane solution, NMR reference standard, 40% in benzene-d₆ (99.6 atom % D), chromium(III) acetylacetonate 5 mg/mL, NMR tube size 5 mm × 8 in.

CRM48367

Supelco

1,4-Dioxane solution, certified reference material, 2000 μg/mL in methanol, ampule of 1 mL