Trifluorosilane induced structural transitions in beta-lactoglobulin in sol and gel.
Fluoroalcohols such as 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) are strong inducers of protein secondary structure. Here, hydrolyzed (3,3,3-trifluoropropyl)trimethoxysilane (3F) is demonstrated to exhibit greater protein conformation inducing activity than HFIP, which is preserved when 3F is copolymerized in tetraethylorthosilicate (TEOS) sol-gels through protein molecular imprinting. Hydrolyzed 3F formed a pre-polymerization complex with the template protein, β-lactoglobulin, inducing distinct α-helical structures as evidenced by circular dichroism. Fluorescence resonance energy transfer between tryptophan and the lipophilic probe 1-anilinonaphthalene-8-sulfonic acid showed a sharp molten globule (MG) transition at 0.2M 3F, whereas HFIP induced a broad MG transition centered at 0.6M HFIP. The 3F-induced BLG conformation transitions were retained upon gelation, validating use of the fluorosilane as a conformation directing functional monomer readily incorporated into sol-gels.
Department of Biological Engineering, Utah State University, Logan, UT 84322, USA.
Yun
Y
Peng
Department of Life, Health and Chemical Sciences, Open University, Milton Keynes MK7 6AA, United Kingdom.
Nicholas W
NW
Turner
Department of Biological Engineering, Utah State University, Logan, UT 84322, USA. Electronic address: dbritt@cc.usu.edu.
David W
DW
Britt
D000817:Anilino Naphthalenesulfonates; D000818:Animals; D002417:Cattle; D031541:Fluorescence Resonance Energy Transfer; D005456:Fluorescent Dyes; D005782:Gels; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007782:Lactoglobulins / Q000737:chemistry*; D054802:Molecular Imprinting; D044367:Phase Transition; D020005:Propanols / Q000737:chemistry*; D017433:Protein Structure, Secondary; D012821:Silanes / Q000737:chemistry*; D006845:Hydrocarbons, Fluorinated
D000817:Anilino Naphthalenesulfonates; D005456:Fluorescent Dyes; D005782:Gels; D007782:Lactoglobulins; D020005:Propanols; D012821:Silanes; C514745:3,3,3-trifluoropropyl-trimethoxysilane; C001337:hexafluoroisopropanol; D006845:Hydrocarbons, Fluorinated; C040733:tetraethoxysilane; C027132:1-anilino-8-naphthalenesulfonate
Fluoroalcohol; Fluorosilane; Functional monomer; Protein conformation transition; Sol–gel encapsulation; β-Lactoglobulin