Appearance of a lag period dependent on pH in the expression of the catecholase activity of a polyphenoloxidase extracted in a latent state from Airen grape (Vitis vinifera L.) berries, is revealed, suggesting the hysteretic nature of the enzyme. The lag time was independent of enzyme concentration, indicating that slow pH-induced conformational changes in the protein must occur during assay. Results obtained by varying substrate concentration show that the system presents hyperbolic or cooperative kinetics depending on the pH of the assay.
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http://dx.doi.org/10.1104/pp.98.2.774 | DOI Listing |
Chem Soc Rev
January 2025
Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
DNA is not only a centrally important molecule in biology: the specificity of bonding that allows it to be the primary information storage medium for life has also allowed it to become one of the most promising materials for designing intricate, self-assembling structures at the nanoscale. While the applications of these structures are both broad and highly promising, the self-assembly process itself has attracted interest not only for the practical applications of designing structures with more efficient assembly pathways, but also due to a desire to understand the principles underlying self-assembling systems more generally, of which DNA-based systems provide intriguing and unique examples. Here, we review the fundamental physical principles that underpin the self-assembly process in the field of DNA nanotechnology, with a specific focus on simulation and modelling and what we can learn from them.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Faculty of Materials Engineering and Physics, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland.
Thermoplastic composites have garnered significant attention in various industries due to their exceptional properties, such as recyclability and ease of molding. In particular, biocomposites, which combine biopolymers with natural fibers, represent a promising alternative to petroleum-based materials, offering biodegradability and reduced environmental impact. However, there is limited knowledge regarding the efficacy of joining PLA/PHBV-based biocomposites modified with nanocrystalline cellulose (NCC) using vibration welding, which restricts their potential applications.
View Article and Find Full Text PDFMicromachines (Basel)
November 2024
Southwest Institute of Technology and Engineering, Chongqing 400039, China.
High-k metal oxides are gradually replacing the traditional SiO dielectric layer in the new generation of electronic devices. In this paper, we report the production of five-element high entropy metal oxides (HEMOs) dielectric films by solution method and analyzed the role of each metal oxide in the system by characterizing the film properties. On this basis, we found optimal combination of (AlGaTiYZr)O with the best dielectric properties, exhibiting a low leakage current of 1.
View Article and Find Full Text PDFJ Colloid Interface Sci
April 2025
Key Laboratory of Eco-chemical Engineering, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China. Electronic address:
Despite the ultrahigh theoretical energy density and cost-effectiveness, aprotic lithium-oxygen (Li-O) batteries suffer from slow oxygen redox kinetics at cathodes and large voltage hysteresis. Here, we well-design ultrafine Co nanoparticles supported by N-doped mesoporous hollow carbon nanospindles (Co@HCNs) to serve as efficient electrocatalysts for Li-O battery. Benefiting from strong metal-support interactions, the obtained Co@HCNs manifest high affinity for the LiO intermediate, promoting formation of ultrathin nanosheet-like LiO with low-impedance contact interface on the Co@HCNs cathode surface, which facilitates the reversible decomposition upon charging.
View Article and Find Full Text PDFBiosens Bioelectron
March 2025
College of Pharmacy and International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Chinese Ministry of Education, Jinan University, Guangzhou, 510632, China. Electronic address:
Urinary protein, an important marker for early detection of kidney injury, would change in type and content dynamically with the degree of kidney injury due to the particle size and charge selectivity of the glomerular filtration system, making it significantly valuable for accurate classification and early diagnosis. In this study, we developed a fluorescence sensor (Ami-AuNP/DNAs) based on charge interaction to rapidly identify the progression of kidney injury. When the positively charged Ami-AuNP combines with negatively charged DNAs, fluorescence quenching occurs, and urine proteins that appear compete with the DNAs, leading to fluorescence recovery.
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