The permeability and solute transport characteristics of amphiphilic triblock-polymer vesicles containing the bacterial water-channel protein Aquaporin Z (AqpZ) were investigated. The vesicles were made of a block copolymer with symmetric poly-(2-methyloxazoline)-poly-(dimethylsiloxane)-poly-(2-methyloxazoline) (PMOXA(15)-PDMS(110)-PMOXA(15)) repeat units. Light-scattering measurements on pure polymer vesicles subject to an outwardly directed salt gradient in a stopped-flow apparatus indicated that the polymer vesicles were highly impermeable. However, a large enhancement in water productivity (permeability per unit driving force) of up to approximately 800 times that of pure polymer was observed when AqpZ was incorporated. The activation energy (E(a)) of water transport for the protein-polymer vesicles (3.4 kcal/mol) corresponded to that reported for water-channel-mediated water transport in lipid membranes. The solute reflection coefficients of glucose, glycerol, salt, and urea were also calculated, and indicated that these solutes are completely rejected. The productivity of AqpZ-incorporated polymer membranes was at least an order of magnitude larger than values for existing salt-rejecting polymeric membranes. The approach followed here may lead to more productive and sustainable water treatment membranes, whereas the variable levels of permeability obtained with different concentrations of AqpZ may provide a key property for drug delivery applications.
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http://dx.doi.org/10.1073/pnas.0708762104 | DOI Listing |
Blood Adv
January 2025
The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Cytoskeletal remodeling and mitochondrial bioenergetics play important roles in thrombocytopoiesis and platelet function. Recently, α-actinin-1 mutations have been reported in patients with congenital macrothrombocytopenia. However, the role and underlying mechanism of α-actinin-1 in thrombocytopoiesis and platelet function remain elusive.
View Article and Find Full Text PDFJ Neurol
January 2025
Department of Medical and Surgical Sciences, University of Foggia, 71122, Foggia, Italy.
Background: Multiple sclerosis (MS) involves a complex interplay between immune-mediated inflammation and neurodegeneration. Recent advances in biomarker research have provided new insights into the molecular underpinnings of MS, including ferritin, neurogranin, Triggering Receptor Expressed on Myeloid cells 2 (TREM2), and neurofilaments light chain.
Objectives: This pilot study aims to investigate the levels of these biomarkers in the cerebrospinal fluid (CSF) of MS patients and explore their associations with clinical, cognitive, and optical coherence tomography (OCT) parameters.
J Chem Phys
January 2025
Department of Physics and Materials Science, The University of Memphis, Memphis, Tennessee 38152, USA.
The adhesion of nanoparticles to lipid vesicles causes curvature deformations to the membrane to an extent determined by the competition between the adhesive interaction and the membrane's elasticity. These deformations can extend over length scales larger than the size of a nanoparticle, leading to an effective membrane-curvature-mediated interaction between nanoparticles. Nanoparticles with uniform surfaces tend to aggregate into unidimensionally close-packed clusters at moderate adhesion strengths and endocytose at high adhesion strengths.
View Article and Find Full Text PDFBeilstein J Org Chem
January 2025
Institute of Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
Polysarcosine emerges as a promising alternative to polyethylene glycol (PEG) in biomedical applications, boasting advantages in biocompatibility and degradability. While the self-assembly behavior of block copolymers containing polysarcosine-containing polymers has been reported, their potential for shape transformation remains largely untapped, limiting their versatility across various applications. In this study, we present a comprehensive methodology for synthesizing, self-assembling, and transforming polysarcosine-poly(benzyl glutamate) block copolymers, resulting in the formation of bowl-shaped vesicles, disks, and stomatocytes.
View Article and Find Full Text PDFNano Lett
January 2025
Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Plant genetic engineering methods are critical for food security and biofuel production and to enable molecular farming. Here, we elucidated how polymeric high aspect ratio nanocarriers can enable DNA delivery to plants and transient expression. We demonstrated that a nanocarrier with 20 nm width, 80 nm length, and a polymer-to-DNA ratio of N/P = 3.
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