It has long been appreciated that hydrophobic folding is an important element of protein structure formation. Here it is demonstrated for the first time that the electrochemical or chemical reduction of a nicotinamide in a model protein, which increases hydrophobicity, can drive hydrophobic folding and assembly in such a way as to lift a weight or otherwise contract against a constant tensional force. The model protein, poly[0.73(GVGVP),0.27(GK(NMeN)GVP], can be gamma-irradiation cross-linked to form an elastic matrix which contracts on raising the temperature from below to above the transition range for hydrophobic folding and assembly. On reduction of the N-methyl nicotinamide, (NMeN), the transition temperature range is lowered from above to below 20 degrees C to drive contraction due to hydrophobic folding with the performance of mechanical work.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1006/bbrc.1994.2449 | DOI Listing |
Anal Chem
January 2025
Laboratory of Analytical Chemistry, Department of Chemistry, University of Athens, Athens 157 71, Greece.
This work describes fully integrated multifolding electrochemical paper-based devices (ePADs) for enhanced multiplexed voltammetric determination of heavy metals (Zn(II), Cd(II), and Pb(II)) using tunable passive preconcentration. The paper devices integrate five circular sample preconcentration layers and a 3-electrode electrochemical cell. The hydrophobic barriers of the devices are drawn by pen-plotting with hydrophobic ink, while the electrodes are deposited by screen-printing.
View Article and Find Full Text PDFAcc Chem Res
January 2025
Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada.
ConspectusStructural DNA nanotechnology offers a unique self-assembly toolbox to construct soft materials of arbitrary complexity, through bottom-up approaches including DNA origami, brick, wireframe, and tile-based assemblies. This toolbox can be expanded by incorporating interactions orthogonal to DNA base-pairing such as metal coordination, small molecule hydrogen bonding, π-stacking, fluorophilic interactions, or the hydrophobic effect. These interactions allow for hierarchical and long-range organization in DNA supramolecular assemblies through a DNA-minimal approach: the use of fewer unique DNA sequences to make complex structures.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Ave., 194064 St. Petersburg, Russia.
The 1-anilino-8-naphthalenesulfonate (ANS) fluorescent dye is widely used in protein folding studies due to the significant increase in its fluorescence quantum yield upon binding to protein hydrophobic regions that become accessible during protein unfolding. However, when modeling cellular macromolecular crowding conditions in protein folding experiments in vitro using crowding agents with guanidine hydrochloride (GdnHCl) as the denaturant, the observed changes in ANS spectral characteristics require careful consideration. This study demonstrates that crowding agents can form clusters that interact differently with ANS.
View Article and Find Full Text PDFJ Membr Biol
January 2025
Departamento de Alimentos. División de Ciencias de la Vida, Campus Irapuato-Salamanca, Universidad de Guanajuato, Carretera Irapuato Silao km 9, 36500, Irapuato, Guanajuato, México.
The Cell-Free Protein Synthesis (CFPS) is an innovative technique used to produce various proteins. It has several advantages, including short expression times, no strain engineering is required, and toxic proteins such as membrane proteins can be produced. However, the most important advantage is that it eliminates the need for a living cell as a production system.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
The effects of 1 % xanthan gum (XG) and hydroxypropyl methylcellulose (HPMC) on the physicochemical and structural properties of triticale gluten (TG) during fermentation were investigated. Rheological analysis revealed that the addition of XG or HPMC decreased G' and G″ values, while increasing tanδ and recovery strain of triticale gluten during fermentation. Thermal gravimetric analysis demonstrated that triticale gluten added with XG after fermentation exhibited the highest residual mass, showing a 9.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!