Anomalous sedimentation patterns arise when free ribosomes from sea urchin eggs are centrifuged at high speeds. Pressure-induced dissociation of the ribosomes during sedimentation can explain the peculiar behavior; the assumption of such dissociation also yields estimates of the equilibrium constant (as a function of KCl concentration) and the change in molecular volume (500 +/- 100 ml/mol) in the reaction: subunits right arrow over left arrow ribosome. Such dissociation during centrifugation may explain many experiments in which apparent reduced sedimentation coefficients for ribosomes, and increased coefficients for the subunits, have been ascribed to conformational changes.
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http://dx.doi.org/10.1073/pnas.68.8.1780 | DOI Listing |
Biochim Biophys Acta Bioenerg
January 2025
Institute of Physics, University of Tartu, W. Ostwaldi 1, 50411 Tartu, Estonia; Estonian Academy of Sciences, Kohtu 6, 10130 Tallinn, Estonia. Electronic address:
The resilience of biological systems to fluctuating environmental conditions is a crucial evolutionary advantage. In this study, we examine the thermo- and piezo-stability of the LH1-RC pigment-protein complex, the simplest photosynthetic unit, in three species of phototropic purple bacteria, each containing only this core complex. Among these species, Blastochloris viridis and Blastochloris tepida utilize bacteriochlorophyll b as the main light-harvesting pigment, while Rhodospirillum rubrum relies on bacteriochlorophyll a.
View Article and Find Full Text PDFFood Chem
September 2024
Beijing Key Laboratory for Food Non-thermal processing, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, National Engineering Research Center for Fruit & Vegetable Processing, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China. Electronic address:
This study investigated the effects of high hydrostatic pressure (HHP) on the binding interactions of cyanindin-3-O-glucoside (C3G) to bovine serum albumin, human serum albumin (HSA), bovine lactoferrin, and ovotransferrin. Fluorescence quenching revealed that HHP reduced C3G-binding affinity to HSA, while having a largely unaffected role for the other proteins. Notably, pretreating HSA at 500 MPa significantly increased its dissociation constant with C3G from 24.
View Article and Find Full Text PDFBiotechnol Bioeng
July 2024
Department of Agricultural and Biological Engineering, University of Florida, Gainesville, Florida, USA.
High hydrostatic pressure stabilized galactose oxidase (GaOx) at 70.0-80.0°C against thermal inactivation.
View Article and Find Full Text PDFActa Crystallogr D Struct Biol
February 2024
ESRF, The European Synchrotron, 71 Avenue des Martyrs, 38000 Grenoble, France.
This article describes the High-Pressure Freezing Laboratory for Macromolecular Crystallography (HPMX) at the ESRF, and highlights new and complementary research opportunities that can be explored using this facility. The laboratory is dedicated to investigating interactions between macromolecules and gases in crystallo, and finds applications in many fields of research, including fundamental biology, biochemistry, and environmental and medical science. At present, the HPMX laboratory offers the use of different high-pressure cells adapted for helium, argon, krypton, xenon, nitrogen, oxygen, carbon dioxide and methane.
View Article and Find Full Text PDFHeliyon
July 2023
Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussel, Belgium.
Biomethane is a renewable natural gas substitute produced from biogas. Storage of this sustainable energy vector in confined clathrate hydrates, encapsulated in the pores of a host material, is a highly promising avenue to improve storage capacity and energy efficiency. Herein, a new type of periodic mesoporous organosilica (PMO) nanotubes, referred to as hollow ring PMO (HR-PMO), capable of promoting methane clathrate hydrate formation under mild working conditions (273 K, 3.
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