Breaking hydrogen bond network enhances oxygenic photosynthesis of photosystem II

Fundamental Research, Journal Year: 2025, Volume and Issue: unknown

Published: March 1, 2025

Language: Английский

---

Experimental quantification of nuclear quantum effects on the hydrogen bond of liquid water

Science Advances, Journal Year: 2025, Volume and Issue: 11(14)

Published: April 4, 2025

Nuclear quantum effects (NQEs) significantly influence material properties upon isotopic substitution, particularly with light atoms such as hydrogen. While water is rich in hydrogen, its hydrogen-bonded structure exhibits only moderate NQEs. Simulations ascribe this to competing zero-point energies (ZPEs): Intermolecular ZPEs stabilize hydrogen-bonds, while intramolecular destabilize them. However, experimental validation has been lacking due the difficulty quantifying The air/water interface provides an ideal platform quantify NQEs liquid using surface-specific vibrational spectroscopy. By analyzing excess/depletion of interfacial HOD, H 2 O, and D O molecules one free OH/OD group other H-bonded group, we found that intermolecular ZPE destabilizes hydrogen-bonds by 0.74 ± 0.20 kilojoule per mole isotope substitution from D, stabilizes them 0.78 0.33 mole. This near-complete cancellation explains overall NQE water. thus allows for

Language: Английский

---

Accurate Determination of Isotope Effects on the Dynamics of H-Bond Breaking and Making in Liquid Water

The Journal of Physical Chemistry Letters, Journal Year: 2025, Volume and Issue: unknown, P. 3727 - 3733

Published: April 5, 2025

Isotopic substitution of light hydrogen atoms with heavier deuterium in liquid water renders the resulting liquid, heavy (D2O), poisonous to most organisms when it replaces a critical fraction living organisms. The mechanisms through which disrupts biological function are challenging disentangle experimentally. has long been known affect H-bond dynamics water, but experiments have yet quantify extent differences time scales breaking and making processes between H2O D2O. In this work, we analyze extensive coupled cluster-quality path integral simulations D2O under ambient conditions that grant access unambiguous molecular analyses. We find substantial isotope effects on rates formation breaking, lifetimes, ∼25% slower than H2O. toxicity can thus be ascribed, at least part, effect slowed biochemical reactions.

Language: Английский

---

Water and Collagen: A Mystery Yet to Unfold

Biomacromolecules, Journal Year: 2025, Volume and Issue: unknown

Published: April 10, 2025

Collagen is the most abundant protein in human body and plays an essential role determining mechanical properties of tissues. Both as a monomeric fibrous assemblies, collagen interacts with its surrounding molecules, particular water. Interestingly, while it well established that interaction water strongly influences molecular underlying mechanisms remain largely unknown. Here, we review research conducted over past 30 years on interplay between relevance for tissue properties. We discuss water-collagen relevant time- length scales, ranging from vital stabilizing characteristic triple helix structure to negative impact dehydration A better understanding will help unravel effect mutations defective production collagen-related diseases pinpoint key design features required synthesize collagen-based biomimetic tissues tailored

Language: Английский

---

Serum metabolite levels identify incipient metastatic progression of rectal cancer

Communications Medicine, Journal Year: 2025, Volume and Issue: 5(1)

Published: April 27, 2025

Abstract Background The cellular metabolism undergoes reprogramming during the metastatic process. We hypothesised that serum metabolites at time of primary tumour diagnosis might identify rectal cancer patients prone to progression. Methods One hundred twenty-three from a prospective observational biomarker study were followed up 5 years after entry. have assessed in sampled by 1 H-nuclear magnetic resonance spectroscopy, using internal reference trimethylsilylpropanoic acid for quantification. Results Here we show who develop overt disease more than 6 months elevated levels (Kruskal-Wallis test) alanine ( P = 0.005), lactate 0.023), pyruvate 0.041) and citrate 0.007) compared those without metastases 5-year follow-up or with already sooner diagnosis. Patients above 0.24 mmol/L poorer progression-free survival below < 0.001; log-rank test). Conclusions observe distinct metabolite profile, particular involving best our knowledge shown first clinically, heightened risk metastasis when is diagnosed, offering insights into

Language: Английский

---

The Correlated States Theory of the Hydrophobic Effect

The Journal of Physical Chemistry B, Journal Year: 2025, Volume and Issue: unknown

Published: May 14, 2025

Starting from Frank and Evans' "iceberg" model of hydrophobic hydration small molecules (the "microscopic" effect, HE) published in 1945, much has been done with respect to understanding the nature HE elaborating a quantitative theory able describe thermodynamic profile "signature" for large volume experimental data accumulated date. Generally, three sets approaches addressing this issue were suggested, ranging approval central role water shell complete denial its role, focus placed on solute interactions surrounding water. For reason, some controversy is still present fundamental HE, even at scale. Nevertheless, general tendency past decade seems have shifted toward greater environment determining designated place solute-water as fine-tuning observables. In work, we developed novel view microscopic scale, appearing consequence correlated translational orientational vibration motion, emerging new property hydration/solvation Correlated States Theory HE). We built fully analytical description process, which enabled us quantify extended without employing molecular simulations or any numerical functions core theory. As consequence, our approach provides self-consistent known major manifestations across an temperature range, addresses controversial issues existing date, creates augmentation current knowledge. Most importantly, suggested offers paradigm shift currently dominating views water-water "excluded effect" interactions, first nonempirical proof validity SASA-based computational models hydration/solvation, utilized empirical basis more than 40 years.

Language: Английский

---

Effect of 2H2O solvent on protein conformational sampling linked to catalysis by UDP-glucuronic acid 4-epimerase

Cell Reports Physical Science, Journal Year: 2025, Volume and Issue: unknown, P. 102607 - 102607

Published: May 1, 2025

Language: Английский

---

Clustering and Sorption of Sulfolane and Pyridine onto Silicates

The Journal of Physical Chemistry B, Journal Year: 2025, Volume and Issue: unknown

Published: May 22, 2025

Sulfolane and pyridine are used for sour gas sweetening carbon capture, they found as cocontaminants in groundwater. They known to be miscible water, but their mixing behavior ternary aqueous mixtures containing sulfolane, pyridine, water is unknown. Pyridine sulfolane hydrogen bond acceptors, increase the proportion of molecules that donate bonds mixtures, revealed by Fourier transform infrared spectroscopy. Small-angle neutron scattering demonstrates form molecular clusters water. These have a core-shell structure, with core shell. Computer simulations indicate composed nine molecules, surrounded five six molecules. While does not sorb onto clay minerals absence promotes its sorption. This potentially limits risk migration clayey aquifers copolluted pyridine.

Language: Английский

---

Exploring proteins at soft interfaces and in thin liquid films – From classical methods to advanced applications of reflectometry

Advances in Colloid and Interface Science, Journal Year: 2024, Volume and Issue: 329, P. 103187 - 103187

Published: May 16, 2024

The history of the topic proteins at soft interfaces dates back to 19th century, and until present day, it has continuously attracted great scientific interest. A multitude experimental methods theoretical approaches have been developed serve research progress in this large domain colloid interface science, including area colloids such as foams emulsions. From classical like surface tension adsorption isotherms, pressure-area measurements for spread layers, rheology probing dynamics adsorption, nowadays, advanced surface-sensitive techniques based on spectroscopy, microscopy, reflection light, X-rays neutrons liquid/fluid offers important complementary sources information. Apart from fundamental characteristics protein i.e., excess, nanoscale structure layers interfacial conformations morphologies are pivotal importance extending depth understanding topic. In review article, we provide an extensive overview application three methods, namely, ellipsometry, X-ray reflectometry neutron reflectometry, structural studies water/air water/oil interfaces. main attention is placed development a discussion relevant achievements terms notable results. We attempted cover whole with these techniques, thus, believe should valuable reference fuel ideas wide spectrum researchers different fields where may be relevance.

Language: Английский

---

Theoretical and experimental OD-stretch vibrational spectroscopy of heavy water

The Journal of Chemical Physics, Journal Year: 2024, Volume and Issue: 160(10)

Published: March 11, 2024

In view of the current situation in which OD-stretch vibrational spectra have been scarcely computed with non-polarizable rigid D2O models, we investigate IR and Raman by using a newly-reported model TIP4P/2005-HW. From comparison between calculations experimental data, find excellent performance TIP4P/2005-HW for spectroscopy same manner as TIP4P/2005 H2O, although one may still conveniently employ an alternative method that regards OH putative OD to calculate similar quality from trajectories. We also demonstrate appropriate setting spectral simulation under time-averaging approximation reflects slower dynamics (i.e., motion translation rotation due heavier mass stronger hydrogen bond) than H2O. Moreover, show theoretical established interpretation OH-stretch H2O is finely applicable D2O.

Language: Английский

---