Bacteriorhodopsin (bR) is a light-driven proton pump and a model membrane transport protein. We used time-resolved serial femtosecond crystallography at an x-ray free electron laser to visualize conformational changes in bR from nanoseconds to milliseconds following photoactivation. An initially twisted retinal chromophore displaces a conserved tryptophan residue of transmembrane helix F on the cytoplasmic side of the protein while dislodging a key water molecule on the extracellular side. The resulting cascade of structural changes throughout the protein shows how motions are choreographed as bR transports protons uphill against a transmembrane concentration gradient.
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http://dx.doi.org/10.1126/science.aah3497 | DOI Listing |
J Occup Environ Med
November 2024
University of Connecticut, Storrs, Connecticut, USA.
Objective: The purpose of study was to explore family caregiver perspectives on work-life balance while caring for adults with Parkinson's Disease.
Methods: The study was performed using a convergent mixed methods design and a revised adaptation of the Work-Life Conflict model. Caregivers completed surveys followed by semi-structured interviews (N = 40).
J Neuroophthalmol
November 2024
Ophthalmology Department (AC-C, MF-R, SA-A, RA, BS-D), Seu Maternitat, Hospital Clínic de Barcelona, Universitat de Barcelona, Barcelona, Spain; Faculty of Medicine and Health Sciences (AC-C, SA-A, BS-D), Universitat de Barcelona, Barcelona, Spain; Fundació Per La Recerca Biomèdica-IDIBAPS (MF-R, SA-A, BS-D), Barcelona, Spain; and Ophthalmology Department (MS-G), Consorci Mar Parc de Salut de Barcelona, Barcelona, Spain.
Background: Autosomal Dominant Optic Atrophy (ADOA) is a hereditary optic neuropathy characterized by retinal ganglion cell degeneration and optic nerve fiber loss. This study examined the correlation between clinical and structural parameters in patients with ADOA using optical coherence tomography (OCT) and explored potential clinical biomarkers.
Methods: A cross-sectional, case-control observational study included 27 patients with ADOA and 27 age- and sex-matched healthy controls.
Proc Natl Acad Sci U S A
January 2025
Department of Molecular & Cellular Biosciences, University of Cincinnati, Cincinnati, OH 45267.
TGFβ family ligands are synthesized as precursors consisting of an N-terminal prodomain and C-terminal growth factor (GF) signaling domain. After proteolytic processing, the prodomain typically remains noncovalently associated with the GF, sometimes forming a high-affinity latent procomplex that requires activation. For the TGFβ family ligand anti-Müllerian hormone (AMH), the prodomain maintains a high-affinity interaction with its GF that does not render it latent.
View Article and Find Full Text PDFAcc Chem Res
January 2025
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
ConspectusReactions of gas phase molecules with surfaces play key roles in atmospheric and environmental chemistry. Reactive uptake coefficients (γ), the fraction of gas-surface collisions that yield a reaction, are used to quantify the kinetics in these heterogeneous and multiphase systems. Unlike rate coefficients for homogeneous gas- or liquid-phase reactions, uptake coefficients are system- and observation-dependent quantities that depend upon a multitude of underlying elementary steps.
View Article and Find Full Text PDFPLoS Genet
January 2025
Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada.
The synaptonemal complex (SC) is a protein-rich structure essential for meiotic recombination and faithful chromosome segregation. Acting like a zipper to paired homologous chromosomes during early prophase I, the complex is a symmetrical structure where central elements are connected on two sides by the transverse filaments to the chromatin-anchoring lateral elements. Despite being found in most major eukaryotic taxa implying a deeply conserved evolutionary origin, several components of the complex exhibit unusually high rates of sequence turnover.
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