Disulfide bonds and calcium ions contribute significantly to the stability of the hemocyanin from the mollusc Rapana thomasiana grosse (gastropod). An extremely powerful protective effect of Ca2+ at a concentration of 100 mM (100% protection) against the destructive effect of reductants like dithiothreitol was observed. This is important for the practical application of molluscan hemocyanins in experimental biochemistry, immunology and medicine. The reduction of the disulfide bonds in the Rapana hemocyanin leads to a 20% decrease of the a-helical structure. The S-S bonds contribute significantly to the free energy of stabilization in water increasing delta G(D)H2O by 6.9 kJ mol (-1) The data are related to the X-ray model of the Rapana hemocyanin functional unit RtH2e. The results of this study can be of common validity for related respiratory proteins because the cysteine residues are conserved in all sequences of molluscan hemocyanins published so far.
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http://dx.doi.org/10.1515/znc-2004-3-428 | DOI Listing |
Food Res Int
February 2025
School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China; Bio-resources Key Laboratory of Shaanxi Province, School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong 723001, China; Quanzhou Marine Biotechnology Industry Research Institute, Quanzhou 362700, China. Electronic address:
The purpose of this study was to investigate the mechanism of enhancing gelling properties of low-salt surimi by utilizing the complementary advantages of L-arginine (L-Arg) and microwave (MW) from the perspective of gels' network characteristics. At MW 3 min, the diameters of protein filaments were increased from 0.015 μm to 0.
View Article and Find Full Text PDFFood Res Int
February 2025
Antioxidant Polyphenols Team, Department of Food Engineering, Sichuan University, Chengdu 610065, PR China; The Key Laboratory of Food Science and Technology of Sichuan Province of Education, Sichuan University, Chengdu 610065, PR China. Electronic address:
Effects of catechins with different structure characteristics on the structure and properties of gluten-catechin covalent complex were investigated, and the structure-activity relationship was further explored. Catechins including epicatechin (EC), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and epigallocatechin-3-gallate (EGCG) could successfully covalently bind with gluten through C-N and/or C-S bonds. The physicochemical properties of covalent complex, including particle size, thermal stability, content of free amino groups, free sulfhydryl groups and disulfide bonds, were significantly affected by different catechins, and the action order was: EGCG > ECG > EGC > EC.
View Article and Find Full Text PDFACS Biomater Sci Eng
January 2025
Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical & Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China.
Metal polyphenolic networks (MPNs) are becoming more and more attractive for nontoxic hair dyeing, but their coloring effect is not satisfactory because of the limited interfacial deposition and the absence of internal deposition. Moreover, there is a lack of understanding of the driving factors of the interfacial deposition of MPNs on hair. Herein, we develop a simple yet efficient strategy that transforms disulfide bonds of the hair into thiol groups by thioglycolic acid (TGA) to highly enhance the coloring effect of MPNs at a low temperature.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310058, PR China.
Mechanoluminescent units, when integrated into polymer matrices, undergo structural transformations in response to mechanical force, resulting in changes in fluorescence. This phenomenon holds considerable promise for the development of stress-sensing materials. Despite the high demand for robust, tunable mechanoluminescent mechanophores for force assessment and smart force-responsive materials, strategies for their design and synthesis remain underdeveloped.
View Article and Find Full Text PDFRedox Biol
January 2025
Laboratory for Research in Functional Nutrition, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Av. El Líbano 5524, Macul, Santiago, 7830490, Chile. Electronic address:
Caffeic acid phenethyl ester (CAPE) is a hydrophobic phytochemical typically found in propolis that acts as an antioxidant, anti-inflammatory and cardiovascular protector, among several other properties. However, the molecular entity responsible for recognising CAPE is unknown, and whether that molecular interaction is involved in developing an antioxidant response in the target cells remains an unanswered question. Herein, we hypothesized that a subfamily of TRP ion channels works as the molecular entity that recognizes CAPE at the plasma membrane and allows a fast shift in the antioxidant capacity of intact endothelial cells (EC).
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