F(1)-ATPase is a nanosized biological energy transducer working as part of F(o)F(1)-ATP synthase. Its rotary machinery transduces energy between chemical free energy and mechanical work and plays a central role in the cellular energy transduction by synthesizing most ATP in virtually all organisms. However, information about its energetics is limited compared to that of the reaction scheme. Actually, fundamental questions such as how efficiently F(1)-ATPase transduces free energy remain unanswered. Here, we demonstrated reversible rotations of isolated F(1)-ATPase in discrete 120° steps by precisely controlling both the external torque and the chemical potential of ATP hydrolysis as a model system of F(o)F(1)-ATP synthase. We found that the maximum work performed by F(1)-ATPase per 120° step is nearly equal to the thermodynamical maximum work that can be extracted from a single ATP hydrolysis under a broad range of conditions. Our results suggested a 100% free-energy transduction efficiency and a tight mechanochemical coupling of F(1)-ATPase.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3207686 | PMC |
http://dx.doi.org/10.1073/pnas.1106787108 | DOI Listing |
Phys Rev E
November 2024
Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland and Department of Theoretical Physics, University of Geneva, 1211 Geneva, Switzerland.
From cytoskeletal networks to tissues, many biological systems behave as active materials. Their composition and stress generation is affected by chemical reaction networks. In such systems, the coupling between mechanics and chemistry enables self-organization, for example, into waves.
View Article and Find Full Text PDFPhys Rev E
November 2024
Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA.
We propose a reaction-diffusion system that converts topological information of an active nematic into chemical signals. We show that a curvature-activated reaction dipole is sufficient for creating a system that dynamically senses topology by producing a concentration field possessing local extrema coinciding with ±1/2 defects. The enabling term is analogous to polarization charge density seen in dielectric materials.
View Article and Find Full Text PDFJ Environ Manage
December 2024
Key Laboratory of Power Station Energy Transfer Conversion and System, Ministry of Education, North China Electric Power University, Beijing, 102206, China.
The emissions of flue gas components (such as Hg, SO, HCl) and the generation of hazardous waste fly ash from municipal waste incineration pose a significant threat to environmental integrity. In this study, a mechanochemical method combined with a modifier is innovatively proposed for the modification of fly ash to remove Hg. In the fixed bed adsorption experiment, the removal efficiency of up to 60 percent can be achieved by ball milling (700rap,30min) alone.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
Polycyclic aromatic diradical(oid) molecules are attracting significant attention because of their unique electronic and magnetic properties as well as their applications as functional materials. While diradical(oid) molecules bearing five-membered rings have been extensively investigated, those bearing seven-membered rings are relatively fewer. Herein, we report the synthesis of azapentabenzodihomocorannulene dication and diradical molecules.
View Article and Find Full Text PDFMol Divers
December 2024
Department of Chemistry, Sankalchand Patel University, Visnagar, 384315, Gujarat, India.
In the past, mechanochemical approaches in organic synthesis were largely overlooked, but their perception within the synthetic community has shifted in recent years, marking a trend toward becoming mainstream. Mechanochemical multicomponent organic synthesis has garnered significant interest from both the academic and industrial chemical sectors. The efficiency and environmental friendliness of procedures conducted through mechanical activation have established mechanical procedures as prominent green techniques.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!