The ESCRT machinery mediates membrane remodeling in numerous processes in cells including cell division and nuclear membrane reformation. The identification of ESCRT homologs in Asgard archaea, currently considered the closest prokaryotic relative of eukaryotes, implies a role for ESCRTs in the membrane remodeling processes that occurred during eukaryogenesis. Yet, the function of these distant ESCRT homologs is mostly unresolved.
View Article and Find Full Text PDFA therapeutic glove, which enables medical non-professionals to perform physiotherapeutic gripping and holding movements on patients, would significantly improve the healthcare situation in physiotherapy. The glove aims to detect the orthogonal pressure load and provide feedback to the user. The use of textile materials for the glove assures comfort and a good fit for the user.
View Article and Find Full Text PDFIndividuals with intellectual and developmental disabilities (IDD) often face numerous barriers to dental care, leading to higher rates of untreated caries and periodontal disease. This editorial explores the challenges associated with dental care for individuals with intellectual disabilities and suggests methods to enhance their dental care. Preventive dental care is crucial for maintaining health.
View Article and Find Full Text PDFEmbedding biomolecules in vitreous ice of optimal thickness is critical for structure determination by cryo-electron microscopy. Ice thickness assessment and selection of suitable holes for data collection are currently part of time-consuming preparatory routines performed on expensive electron microscopes. To address this challenge, a routine has been developed to measure ice thickness during sample preparation using an optical camera integrated in the VitroJet.
View Article and Find Full Text PDFVesicle-inducing protein in plastids 1 (Vipp1) is critical for thylakoid membrane biogenesis and maintenance. Although Vipp1 has recently been identified as a member of the endosomal sorting complexes required for transport III superfamily, it is still unknown how Vipp1 remodels membranes. Here, we present cryo-electron microscopy structures of Synechocystis Vipp1 interacting with membranes: seven structures of helical and stacked-ring assemblies at 5-7-Å resolution engulfing membranes and three carpet structures covering lipid vesicles at ~20-Å resolution using subtomogram averaging.
View Article and Find Full Text PDFCryo-transmission electron microscopy (cryo-EM) of frozen hydrated specimens is an efficient method for the structural analysis of purified biological molecules. However, cryo-EM and cryo-electron tomography are limited by the low signal-to-noise ratio (SNR) of recorded images, making detection of smaller particles challenging. For dose-resilient samples often studied in the physical sciences, electron ptychography - a coherent diffractive imaging technique using 4D scanning transmission electron microscopy (4D-STEM) - has recently demonstrated excellent SNR and resolution down to tens of picometers for thin specimens imaged at room temperature.
View Article and Find Full Text PDFSynDLP, a dynamin-like protein (DLP) encoded in the cyanobacterium Synechocystis sp. PCC 6803, has recently been identified to be structurally highly similar to eukaryotic dynamins. To elucidate structural changes during guanosine triphosphate (GTP) hydrolysis, we solved the cryoelectron microscopy (cryo-EM) structures of oligomeric full-length SynDLP after addition of guanosine diphosphate (GDP) at 4.
View Article and Find Full Text PDFEukaryotic members of the endosome sorting complex required for transport-III (ESCRT-III) family have been shown to form diverse higher-order assemblies. The bacterial phage shock protein A (PspA) has been identified as a member of the ESCRT-III superfamily, and PspA homo-oligomerizes to form rod-shaped assemblies. As observed for eukaryotic ESCRT-III, PspA forms tubular assemblies of varying diameters.
View Article and Find Full Text PDFIterative phase retrieval is based on minimising a loss function as a measure of the consistency of an initial guess and underlying experimental data. Under ideal experimental conditions, real data contains Poissonian noise due to counting statistics. In this work, we use the Wirtinger Flow concept in combination with four common loss functions, being the L loss, the mean-squared error (MSE), the amplitude loss and the Poisson loss.
View Article and Find Full Text PDFPurpose: Despite the differences in material properties and shapes among the different types of prefabricated titanium (pTiA) and individualized hybrid zirconia abutments (ihZiA), the biological and clinical relevance of materials and construction features remains vague. Yet, individualized ihZiA are increasingly implemented into daily routine aiming to satisfy rising expectations. The objective was to compare these two types of abutments in fixed dental prostheses (FDP).
View Article and Find Full Text PDFFunctional electrical stimulation (FES) aims to improve the gait pattern in cases of weak foot dorsiflexion (foot lifter weakness) and, therefore, increase the liveability of people suffering from chronic diseases of the central nervous system, e.g., multiple sclerosis.
View Article and Find Full Text PDFIn situ cryo-electron tomography (cryo-ET) is the most current, state-of-the-art technique to study cell machinery in its hydrated near-native state. The method provides ultrastructural details at sub-nanometer resolution for many components within the cellular context. Making use of recent advances in sample preparation techniques and combining this method with correlative light and electron microscopy (CLEM) approaches have enabled targeted molecular visualization.
View Article and Find Full Text PDFNEMO is a ubiquitin-binding protein which regulates canonical NF-κB pathway activation in innate immune signaling, cell death regulation and host-pathogen interactions. Here we identify an NF-κB-independent function of NEMO in proteostasis regulation by promoting autophagosomal clearance of protein aggregates. NEMO-deficient cells accumulate misfolded proteins upon proteotoxic stress and are vulnerable to proteostasis challenges.
View Article and Find Full Text PDFAutophagy-related protein 18 (Atg18) participates in the elongation of early autophagosomal structures in concert with Atg2 and Atg9 complexes. How Atg18 contributes to the structural coordination of Atg2 and Atg9 at the isolation membrane remains to be understood. Here, we determined the cryo-EM structures of Atg18 organized in helical tubes, Atg18 oligomers in solution as well as on lipid membrane scaffolds.
View Article and Find Full Text PDFRecently, there has been remarkable progress in the development of smart textiles, especially knitted strain sensors, to achieve reliable sensor signals. Stable and reliable electro-mechanical properties of sensors are essential for using textile-based sensors in medical applications. However, the challenges associated with significant hysteresis and low gauge factor (GF) values remain for using strain sensors for motion capture.
View Article and Find Full Text PDFTrends Biochem Sci
November 2023
Structural and evolutionary studies of cyanobacterial phage shock protein A (PspA) and inner membrane-associated protein of 30 kDa (IM30) have revealed that these proteins belong to the endosomal sorting complex required for transport-III (ESCRT-III) superfamily, which is conserved across all three domains of life. PspA and IM30 share secondary and tertiary structures with eukaryotic ESCRT-III proteins, whilst also oligomerizing via conserved interactions. Here, we examine the structures of bacterial ESCRT-III-like proteins and compare the monomeric and oligomerized forms with their eukaryotic counterparts.
View Article and Find Full Text PDFPseudomonas species have become promising cell factories for the production of natural products due to their inherent robustness. Although these bacteria have naturally evolved strategies to cope with different kinds of stress, many biotechnological applications benefit from engineering of optimised chassis strains with specially adapted tolerance traits. Here, we explored the formation of outer membrane vesicles (OMV) of Pseudomonas putida KT2440.
View Article and Find Full Text PDFUnlabelled: An unanswered question with open tibial fractures is whether the type of flap used affects hardware retention. Flap survival may not equate hardware retention or limb salvage. In this study, we performed a 10-year single institution review and analysis of all patients who had placement of hardware for open tibial fractures followed by flap coverage.
View Article and Find Full Text PDFStructure determination of biological macromolecules using cryogenic electron microscopy is based on applying the phase object (PO) assumption and the weak phase object (WPO) approximation to reconstruct the 3D potential density of the molecule. To enhance the understanding of image formation of protein complexes embedded in glass-like ice in a transmission electron microscope, this study addresses multiple scattering in tobacco mosaic virus (TMV) specimens. This includes the propagation inside the molecule while also accounting for the effect of structural noise.
View Article and Find Full Text PDFObjectives: This study aimed to evaluate the influence of vestibuloplasty on the clinical success and survival of dental implants in head and neck tumor patients.
Materials And Methods: A retrospective single-center study was conducted. All patients received surgical therapy of a tumor in the head or neck and underwent surgical therapy and, if necessary, radiotherapy/radiochemotherapy.
Background: Chlamydia (C.) psittaci, the causative agent of avian chlamydiosis and human psittacosis, is a genetically heterogeneous species. Its broad host range includes parrots and many other birds, but occasionally also humans (via zoonotic transmission), ruminants, horses, swine and rodents.
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