The effect of spermine on proton transport across large unilamellar liposomes containing incorporated complexes of the PSII antenna has been studied with the application of a pH-sensitive dye entrapped inside the vesicles. Both monomeric LHCbs and trimeric LHCII increased the permeability of proteoliposomes to protons when in a partly aggregated state within the lipid membrane. We have previously shown that a spermine-induced conformational change in LHCII results in its aggregation and ultimately in the enhancement of excitation energy as heat (qE). In this paper, spermine-induced aggregation of LHCII was found to facilitate proton transport across the proteoliposomes, indicating that a second protective mechanism (other than qE) might exist and might be regulated in vivo by polyamines when photosynthesis is saturated in excess light.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.jplph.2015.01.010 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Engineered Passive Glucose Uptake in Pseudomonas taiwanensis VLB120 Increases Resource Efficiency for Bioproduction.
Microb Biotechnol
January 2025
Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany.
Glucose is the most abundant monosaccharide and a principal substrate in biotechnological production processes. In Pseudomonas, this sugar is either imported directly into the cytosol or first oxidised to gluconate in the periplasm. While gluconate is taken up via a proton-driven symporter, the import of glucose is mediated by an ABC-type transporter, and hence both require energy.
View Article and Find Full Text PDFProbing Impact of Support Pore Diameter on Three-phase Interfaces of Pt/C Catalysts by Molecular Dynamic Simulation.
ACS Appl Mater Interfaces
January 2025
State Key Laboratory of Advanced Chemical Power Sources (Chongqing University), Chongqing 400044, China.
Investigating how the size of carbon support pores influences the three-phase interface of platinum (Pt) particles in fuel cells is essential for enhancing catalyst utilization. This study employed molecular dynamics simulations and density functional theory calculation to examine the effects of mesoporous carbon support size, specifically its pore diameter, on Nafion ionomer distribution, as well as on proton and gas/liquid transport channels, and the utilization of Pt active sites. The findings show that when Pt particles are located within the pores of carbon support (Pt/PC), there is a significant enhancement in the spatial distribution of Nafion ionomer, along with a reduction in encapsulation around the Pt particles, compared to when Pt particles are positioned on the surface or in excessively large pores of the carbon support.
View Article and Find Full Text PDFSpecificity and tunability of efflux pumps: A new role for the proton gradient?
PLoS Comput Biol
January 2025
Department of Physics, University of Toronto, Toronto, Ontario, Canada.
Efflux pumps that transport antibacterial drugs out of bacterial cells have broad specificity, commonly leading to broad spectrum resistance and limiting treatment strategies for infections. It remains unclear how efflux pumps can maintain this broad spectrum specificity to diverse drug molecules while limiting the efflux of other cytoplasmic content. We have investigated the origins of this broad specificity using theoretical models informed by the experimentally determined structural and kinetic properties of efflux pumps.
View Article and Find Full Text PDFProbing the Influence of the Protein Scaffold on H-Cluster Reactivity via Gain-of-Function Studies─Improved H Evolution and O Tolerance through Rational Design of [FeFe] Hydrogenase.
J Am Chem Soc
January 2025
Molecular Biomimetics, Department of Chemistry, Ångström Laboratory, Uppsala University, P.O. Box 523, Uppsala SE-75120, Sweden.
[FeFe] hydrogenases make up a structurally diverse family of metalloenzymes that catalyze proton/dihydrogen interconversion. They can be classified into phylogenetically distinct groups denoted A-G, which differ in structure and reactivity. Prototypical Group A hydrogenases have high turnover rates and remarkable energy efficiency.
View Article and Find Full Text PDFUnravelling OsPHT2;1 function in Chloroplast Phosphorus Homeostasis and Photosynthetic Efficiency under Low Phosphorus Stress in Rice.
Physiol Plant
January 2025
College of Life Sciences, Nanjing Agricultural University, Nanjing, China.
Phosphorus (P) deficiency is a critical factor limiting crop productivity, primarily due to its detrimental effects on photosynthesis and dry matter accumulation. In this study, we investigate the role of the rice gene OsPHT2;1 in mediating chloroplast P homeostasis and its subsequent impact on photosynthetic function under low P conditions. Stomatal conductance is typically positively correlated with net photosynthetic rates; however, P deficiency disrupts this relationship, leading to reduced stomatal opening and diminished photosynthetic efficiency.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!