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Nature Nov 2023Optimum protein function and biochemical activity critically depends on water availability because solvent thermodynamics drive protein folding and macromolecular...
Optimum protein function and biochemical activity critically depends on water availability because solvent thermodynamics drive protein folding and macromolecular interactions. Reciprocally, macromolecules restrict the movement of 'structured' water molecules within their hydration layers, reducing the available 'free' bulk solvent and therefore the total thermodynamic potential energy of water, or water potential. Here, within concentrated macromolecular solutions such as the cytosol, we found that modest changes in temperature greatly affect the water potential, and are counteracted by opposing changes in osmotic strength. This duality of temperature and osmotic strength enables simple manipulations of solvent thermodynamics to prevent cell death after extreme cold or heat shock. Physiologically, cells must sustain their activity against fluctuating temperature, pressure and osmotic strength, which impact water availability within seconds. Yet, established mechanisms of water homeostasis act over much slower timescales; we therefore postulated the existence of a rapid compensatory response. We find that this function is performed by water potential-driven changes in macromolecular assembly, particularly biomolecular condensation of intrinsically disordered proteins. The formation and dissolution of biomolecular condensates liberates and captures free water, respectively, quickly counteracting thermal or osmotic perturbations of water potential, which is consequently robustly buffered in the cytoplasm. Our results indicate that biomolecular condensation constitutes an intrinsic biophysical feedback response that rapidly compensates for intracellular osmotic and thermal fluctuations. We suggest that preserving water availability within the concentrated cytosol is an overlooked evolutionary driver of protein (dis)order and function.
Topics: Cell Death; Cytosol; Homeostasis; Macromolecular Substances; Osmolar Concentration; Pressure; Proteins; Solvents; Temperature; Thermodynamics; Time Factors; Water
PubMed: 37853127
DOI: 10.1038/s41586-023-06626-z -
Journal of Materials Chemistry. B Jun 2023Dipeptides are attractive building blocks for biomaterials in light of their inherent biocompatibility, biodegradability, and simplicity of preparation. Since the... (Review)
Review
Dipeptides are attractive building blocks for biomaterials in light of their inherent biocompatibility, biodegradability, and simplicity of preparation. Since the discovery of diphenylalanine (Phe-Phe) self-assembling ability into nanotubes, research efforts have been devoted towards the identification of other dipeptide sequences capable of forming these interesting nanomorphologies, although design rules towards nanotube formation are still elusive. In this review, we analyze the dipeptide sequences reported thus far for their ability to form nanotubes, which often feature water-filled supramolecular channels as revealed by single-crystal X-ray diffraction, as well as their properties, and their potential biological applications, which span from drug delivery and regenerative medicine, to bioelectronics and bioimaging.
Topics: Nanotubes; Water; Dipeptides; Models, Molecular; Hydrogen Bonding; Humans; Amino Acids
PubMed: 36790014
DOI: 10.1039/d2tb02643k -
Biochimica Et Biophysica Acta.... Feb 2024Water is essential for all life because it is required for the proper functioning of the cells and tissues of all organisms. It crosses biological membranes down osmotic...
Water is essential for all life because it is required for the proper functioning of the cells and tissues of all organisms. It crosses biological membranes down osmotic gradients through the pores of aquaporin membrane channels at rates of up to 3 billion molecules per second. In the twenty years since Peter Agre was awarded the 2003 Nobel Prize in Chemistry for the discovery of the aquaporin family, aquaporin structure and function have become established in the literature. As a consequence, we understand in fine detail the mechanism by which aquaporins facilitate membrane water flow while excluding protons. We also know that some aquaporins facilitate the permeation of other small neutral solutes, ions or even unexpected substrates across biological membranes. The thirteen aquaporins in the human body have been implicated in pathologies including oedema, epilepsy, cancer cell migration, tumour angiogenesis, metabolic disorders and inflammation. Surprisingly, however, there is no aquaporin-targeted drug in the clinic. Some scientists have therefore concluded that aquaporins are intrinsically non-druggable targets. Discovering medicines to treat disorders of water homeostasis is thus an enduring challenge for the aquaporin field. Success in this endeavour will meet the urgent clinical need of millions of patients suffering from a range of life-threatening conditions and for whom no pharmacological interventions are currently available.
Topics: Humans; Aquaporins; Cell Membrane; Homeostasis; Water
PubMed: 37146744
DOI: 10.1016/j.bbamem.2023.184164 -
Biomolecules Dec 2023Collagen is a triple-helical protein unique to the extracellular matrix, conferring rigidity and stability to tissues such as bone and tendon. For the [(PPG)10]3...
Collagen is a triple-helical protein unique to the extracellular matrix, conferring rigidity and stability to tissues such as bone and tendon. For the [(PPG)10]3 collagen-mimetic peptide at room temperature, our molecular dynamics simulations show that these properties result in a remarkably ordered first hydration layer of water molecules hydrogen bonded to the backbone carbonyl (bb-CO) oxygen atoms. This originates from the following observations. The radius of gyration attests that the PPG triplets are organized along a straight line, so that all triplets (excepting the ends) are equivalent. The solvent-accessible surface area (SASA) for the bb-CO oxygens shows a repetitive regularity for every triplet. This leads to water occupancy of the bb-CO sites following a similar regularity. In the crystal-phase X-ray data, as well as in our 100 K simulations, we observe a 0-2-1 water occupancy in the P-P-G triplet. Surprisingly, a similar (0-1.7-1) regularity is maintained in the liquid phase, in spite of the sub-nsec water exchange rates, because the bb-CO sites rarely remain vacant. The manifested ordered first-shell water molecules are expected to produce a cylindrical electrostatic potential around the peptide, to be investigated in future work.
Topics: Peptides; Water; Solvents; Chemical Phenomena; Collagen
PubMed: 38136615
DOI: 10.3390/biom13121744 -
International Journal of Molecular... Mar 2024Water is an abundant and important component of the human brain, the homeostasis of which is rigorously controlled [...].
Water is an abundant and important component of the human brain, the homeostasis of which is rigorously controlled [...].
Topics: Humans; Aquaporins; Brain Diseases; Water; Homeostasis; Brain
PubMed: 38542489
DOI: 10.3390/ijms25063513 -
Journal of Environmental Management Jul 2023Examples of successful mine closure and acceptable regional transitioning of mining areas are scarce. The recent changes to the environmental, social and governance... (Review)
Review
Examples of successful mine closure and acceptable regional transitioning of mining areas are scarce. The recent changes to the environmental, social and governance (ESG) obligations of mining companies should help to ensure that water and land resources as well as post-mining employment opportunities are considered as a part of mine closure. Integrating microalgae production into mine closure plans is a potential opportunity for mining companies to improve many ESG outcomes. Mine sites with sufficient suitable land and water resources in high solar radiation geographies may be able to economically grow microalgae to capture atmospheric CO, re-purpose saline mine waters, treat acidic and near-neutral pH metalliferous waters as well as produce soil ameliorants (biofertiliser, biostimulants and/or biochar) to improve mine rehabilitation outcomes. Microalgae production facilities may also provide an alternative industry and employment opportunities to help transition regional mining towns that have become reliant on mining activities. The potential economic, environmental and social benefits of using mine-influenced water for microalgae production may offer an opportunity to successfully close and transition some mining landscapes.
Topics: Microalgae; Soil; Metals; Mining; Water; Environmental Monitoring
PubMed: 36933531
DOI: 10.1016/j.jenvman.2023.117736 -
International Journal of Molecular... Jun 2023The frequency range of terahertz waves (THz waves) is between 0.1 and 10 THz and they have properties such as low energy, penetration, transients, and spectral... (Review)
Review
The frequency range of terahertz waves (THz waves) is between 0.1 and 10 THz and they have properties such as low energy, penetration, transients, and spectral fingerprints, which are especially sensitive to water. Terahertz, as a frontier technology, have great potential in interpreting the structure of water molecules and detecting biological water conditions, and the use of terahertz technology for water detection is currently frontier research, which is of great significance. Firstly, this paper introduces the theory of terahertz technology and summarizes the current terahertz systems used for water detection. Secondly, an overview of theoretical approaches, such as the relaxation model and effective medium theory related to water detection, the relationship between water molecular networks and terahertz spectra, and the research progress of the terahertz detection of water content and water distribution visualization, are elaborated. Finally, the challenge and outlook of applications related to the terahertz wave detection of water are discussed. The purpose of this paper is to explore the research domains on water and its related applications using terahertz technology, as well as provide a reference for innovative applications of terahertz technology in moisture detection.
Topics: Water; Technology
PubMed: 37446112
DOI: 10.3390/ijms241310936 -
International Journal of Molecular... Jul 2023Water is a key actor of various processes of nature and, therefore, molecular engineering has to take the structural and energetic consequences of hydration into... (Review)
Review
Water is a key actor of various processes of nature and, therefore, molecular engineering has to take the structural and energetic consequences of hydration into account. While the present review focuses on the target-ligand interactions in drug design, with a focus on biomolecules, these methods and applications can be easily adapted to other fields of the molecular engineering of molecular complexes, including solid hydrates. The review starts with the problems and solutions of the determination of water structures. The experimental approaches and theoretical calculations are summarized, including conceptual classifications. The implementations and applications of water models are featured for the calculation of the binding thermodynamics and computational ligand docking. It is concluded that theoretical approaches not only reproduce or complete experimental water structures, but also provide key information on the contribution of individual water molecules and are indispensable tools in molecular engineering.
Topics: Water; Protein Binding; Ligands; Drug Design; Thermodynamics
PubMed: 37511543
DOI: 10.3390/ijms241411784 -
Environmental Science & Technology Jul 2023Halogenated estrogens are formed during chlorine-based wastewater disinfection and have been detected in wastewater treatment plant effluent; however, very little is...
Halogenated estrogens are formed during chlorine-based wastewater disinfection and have been detected in wastewater treatment plant effluent; however, very little is known about their susceptibility to biodegradation in natural waters. To better understand the biodegradation of free and halogenated estrogens in a large river under environmentally relevant conditions, we measured estrogen kinetics in aerobic microcosms containing water and sediment from the Willamette River (OR, USA) at two concentrations (50 and 1250 ng L). Control microcosms were used to characterize losses due to sorption and other abiotic processes, and microbial dynamics were monitored using 16S rRNA gene sequencing and ATP. We found that estrogen biodegradation occurred on timescales of hours to days and that in river water spiked at 50 ng L half-lives were significantly shorter for 17β-estradiol ( = 42 ± 3 h) compared to its monobromo ( = 49 ± 5 h), dibromo ( = 88 ± 12 h), and dichloro ( = 98 ± 16 h) forms. Biodegradation was also faster in microcosms with high initial estrogen concentrations as well as those containing sediment. Free and halogenated estrone were important transformation products in both abiotic and biotic microcosms. Taken together, our findings suggest that biodegradation is a key process for removing free estrogens from surface waters but likely plays a much smaller role for the more highly photolabile halogenated forms.
Topics: Estrogens; Rivers; RNA, Ribosomal, 16S; Water Pollutants, Chemical; Biodegradation, Environmental; Water
PubMed: 37428977
DOI: 10.1021/acs.est.3c00801 -
Sensors (Basel, Switzerland) Jun 2023Agriculture is a major consumer of freshwater and is often associated with low water productivity. To prevent drought, farmers tend to over-irrigate, putting a strain on...
Agriculture is a major consumer of freshwater and is often associated with low water productivity. To prevent drought, farmers tend to over-irrigate, putting a strain on the ever-depleting groundwater resources. To improve modern agricultural techniques and conserve water, quick and accurate estimates of soil water content (SWC) should be made, and irrigation timed correctly in order to optimize crop yield and water use. In this study, soil samples common to the Maltese Islands having different clay, sand, and silt contents were, primarily, investigated to: (a) deduce whether the dielectric constant can be considered as a viable indicator of the SWC for the soils of Malta; (b) determine how soil compaction affects the dielectric constant measurements; and (c) to create calibration curves to directly relate the dielectric constant and the SWC for two different soil types of low and high density. The measurements, which were carried out in the X-band, were facilitated by an experimental setup comprising a two-port Vector Network Analyzer (VNA) connected to a rectangular waveguide system. From data analysis, it was found that for each soil investigated, the dielectric constant increases notably with an increase in both density and SWC. Our findings are expected to aid in future numerical analysis and simulations aimed at developing low-cost, minimally invasive Microwave (MW) systems for localized SWC sensing, and hence, in agricultural water conservation. However, it should be noted that a statistically significant relationship between soil texture and the dielectric constant could not be determined at this stage.
Topics: Soil; Agriculture; Clay; Groundwater; Water
PubMed: 37300083
DOI: 10.3390/s23115357