Design and Simulation of a Piezoresistive v-Shaped Strain Gauge for Torque Measring

Modeling and simulation of system design adjustment is respectable training for design and engineering decisions in real world jobs. In this paper, the exact perseverance connected with the strain of components is very important for structural designs, analyses, and for excellent control. The information linked to this type of test is usually related to the exact dimensions connected with the pressure within a flexible region. This paper proposed the design and simulation of a torque sensor with a piezoresistive V-shaped strain gauge. The piezoresistive measure of a precious metal for a stable base was made according to the results of an ANSYS simulation. A torque sensor with a piezoresistive V-shaped tension measure on a base was made. The result of the particular simulation shifted the fraction of tension on the base to enable the torque on the substrate to be measured. Theoretical studies on the piezoresistive measure of a metal for the stable base as well as the torque sensor were introduced. A maximum of 127.29 με and a maximum resistance change in gauge equal to 0.091Ω were achieved for an applied torque of 22.0725 Nm. Here, computer systems modeling and simulation are going to be used.

Two functional epithelial sodium channel isoforms are present in rodents despite pronounced evolutionary pseudogenisation and exon fusion

The epithelial sodium channel (ENaC) plays a key role in salt and water homeostasis in tetrapod vertebrates. There are four ENaC subunits (α, β, γ, δ), forming heterotrimeric αβγ- or δβγ-ENaCs. While the physiology of αβγ-ENaC is well understood, for decades the field has stalled with respect to δβγ-ENaC due to the lack of mammalian model organisms. The SCNN1D gene coding for δ-ENaC was previously believed to be absent in rodents, hindering studies using standard laboratory animals. We analysed all currently available rodent genomes and discovered that SCNN1D is present in rodents but was independently lost in five rodent lineages, including the Muridae (mice and rats). The independent loss of SCNN1D in rodent lineages may be constrained by phylogeny and taxon-specific adaptation to dry habitats, however habitat aridity does not provide a selection pressure for maintenance of SCNN1D across Rodentia. A fusion of two exons coding for a structurally flexible region in the extracellular domain of δ-ENaC appeared in the Hystricognathi (a group that includes guinea pigs). This conserved pattern evolved at least 41 Ma ago and represents a new autapomorphic feature for this clade. Exon fusion does not impair functionality of guinea pig (Cavia porcellus) δβγ-ENaC expressed in Xenopus oocytes. Electrophysiological characterisation at the whole-cell and single-channel level revealed conserved biophysical features and mechanisms controlling guinea pig αβγ- and δβγ-ENaC function as compared to human orthologues. Guinea pigs therefore represent commercially available mammalian model animals that will help shed light on the physiological function of δ-ENaC.

Interaction of the TonB dependent transporter HasR with its cognate TonB-like protein HasB in a membrane environment

Energized nutrient import in bacteria needs the interaction between a TonB-dependent transporter (TBDT) and a TonB protein. The mechanism of energy and signal transfer between these two proteins is not well understood. They belong to two membranes separated by the periplasmic space and possess each a disordered and flexible region. Therefore, the membranes, their distance and geometrical constraints together with the protein dynamics are important factors for deciphering this trans-envelope system. Here we report the first example of the interaction of a TBDT with a TonB protein in the presence of both membranes. By combining molecular dynamics simulations in a membrane model, in vitro and in vivo phenotypic experiments we obtained the comprehensive network of interaction between HasR, a heme/hemophore receptor and its dedicated TonB protein, HasB.

An Innovative antibody-based Plug-and-Play strategy for SARS-CoV-2

The novel and highly pathogenic coronavirus (SARS-CoV-2) remains a public health threat worldwide. SARS-CoV-2 enters human host lung cells via its spike protein binding to angiotensin-converting enzyme 2 (ACE2) in a process critical dependent on host protease-mediated fusion event. Thus, effective targeted therapies blocking the first step of viral fusion and cellular entry remains a critical unmet medical need to overcome disease pathology. Here we engineered and describe an antibody-based novel and targeted plug-and-play strategy, which directly competes with the proteolytic activation function of SAR-CoV-2 spike protein. The described strategy involves the engineering of furin substrate residues in IgG1 Fc-extended flexible region of spike targeting antibody. Our results with spike receptor-binding domain (RBD) targeting CR3022 antibody support blockade of the viral function using proof of concept ACE2 overexpressing cells. Our study reveals analytical, safe, and selective mechanistic insights for SARS-CoV-2 therapeutic design and is broadly applicable to the future coronaviridae family members (including mutant variants) exploiting the host protease system for cellular entry.

Structural Insight on Functional Regulation of Human MINERVA Protein

MINERVA (melanoma invasion by ERK), also known as FAM129B, is a member of the FAM129 protein family, which is only present in vertebrates. MINERVA is involved in key signaling pathways regulating cell survival, proliferation and apoptosis and found upregulated in many types of cancer promoting invasion. However, the exact function of the protein remains elusive. X-ray crystallographic methods were implemented to determine the crystal structure of MINERVAΔC, lacking C-terminal flexible region. Trypsin digestion was required before crystallization to obtain diffraction-quality crystals. While the N-terminal pleckstrin homology (PH) domain exhibits the typical fold of PH domains, lipid binding assay indicates specific affinity towards phosphatidic acid and inositol 3-phosphate. A helix-rich domain that constitutes the rest of the molecule demonstrates a novel L-shaped fold that encompasses the PH domain. The overall structure of MINERVAΔC with binding assays and cell-based experiments suggest plasma membrane association of MINERVA and its function seem to be tightly regulated by various motifs within the C-terminal flexible region. Elucidation of MINERVAΔC structure presents a novel fold for an α-helix bundle domain that would provide a binding platform for interacting partners.

Research on Renewable Energy Planning Considering the Flexible Region of the Microgrid

A microgrid can effectively improve the system reliability of a distribution network. When a fault occurs, the microgrid only has a determined division scheme under a fixed boundary method, and it is difficult to adapt to the random load and distributed power. In this paper, a novel renewable energy planning method considering the flexible region of the microgrid is proposed. Based on the randomness of the load and the output of distributed generations (DG) in the microgrid, the dynamic division method of the microgrid is proposed and the optimal allocation model of the distributed energy in the microgrid is established. Further, the model and method proposed are verified by the IEEE-33 bus test system. The simulation results show that the allocation of renewable energy in the microgrid considering the flexible region of the microgrid can effectively increase the utilization of renewable energy and improve the reliability of microgrid operation.

The N-terminus of varicella-zoster virus glycoprotein B has a functional role in fusion

Varicella-zoster virus (VZV) is a medically important alphaherpesvirus that induces fusion of the virion envelope and the cell membrane during entry, and between cells to form polykaryocytes within infected tissues during pathogenesis. All members of the Herpesviridae, including VZV, have a conserved core fusion complex composed of glycoproteins, gB, gH and gL. The ectodomain of the primary fusogen, gB, has five domains, DI-V, of which DI contains the fusion loops needed for fusion function. We recently demonstrated that DIV is critical for fusion initiation, which was revealed by a 2.8Å structure of a VZV neutralizing mAb, 93k, bound to gB and mutagenesis of the gB-93k interface. To further assess the mechanism of mAb 93k neutralization, the binding site of a non-neutralizing mAb to gB, SG2, was compared to mAb 93k using single particle cryogenic electron microscopy (cryo-EM). The gB-SG2 interface partially overlapped with that of gB-93k but, unlike mAb 93k, mAb SG2 did not interact with the gB N-terminus, suggesting a potential role for the gB N-terminus in membrane fusion. The gB ectodomain structure in the absence of antibody was defined at near atomic resolution by single particle cryo-EM (3.9Å) of native full-length gB purified from infected cells and by X-ray crystallography (2.4Å) of the transiently expressed ectodomain. Both structures revealed that the VZV gB N-terminus (aa72-114) was flexible based on the absence of visible structures in the cryo-EM or X-ray crystallography data but the presence of gB N-terminal peptides were confirmed by mass spectrometry. Notably, N-terminal residues 109KSQD112 were predicted to form a small α-helix and alanine substitution of these residues abolished cell-cell fusion in a virus-free assay. Importantly, transferring the 109AAAA112 mutation into the VZV genome significantly impaired viral propagation. These data establish a functional role for the gB N-terminus in membrane fusion broadly relevant to the Herpesviridae.Author SummaryHerpesviruses are ubiquitous infectious agents of medical and economic importance, including varicella-zoster virus (VZV), which causes chicken pox and shingles. A unifying theme of herpesviruses is their mechanism of entry into host cells, membrane fusion, via a core complex of virally expressed envelope glycoproteins gB, gH and gL. Of these, the primary fusogen, gB, is activated by the heterodimer gH-gL through an unknown mechanism and enables the virus envelope to merge with cell membranes to release the DNA containing capsid into the cytoplasm to initiate infection. By using a human antibody that neutralizes VZV we have recently demonstrated that the initiation of membrane fusion is associated with the crown region of gB. Here, we use cryogenic electron microscopy to compare the structure of this human neutralizing antibody, 93k, to a non-neutralizing antibody SG2. Surprisingly, both antibodies bind to the crown of gB with considerable overlap of their footprints on gB with one important exception, SG2 does not bind to a flexible region in the gB N-terminus. Mutations incorporated into this flexible region disrupts gB mediated membrane fusion and significantly impairs VZV propagation, identifying an Achilles heel in viral replication.

In-cell destabilization of a homodimeric protein complex detected by DEER spectroscopy

The complexity of the cellular medium can affect proteins’ properties, and, therefore, in-cell characterization of proteins is essential. We explored the stability and conformation of the first baculoviral IAP repeat (BIR) domain of X chromosome-linked inhibitor of apoptosis (XIAP), BIR1, as a model for a homodimer protein in human HeLa cells. We employed double electron–electron resonance (DEER) spectroscopy and labeling with redox stable and rigid Gd3+spin labels at three representative protein residues, C12 (flexible region), E22C, and N28C (part of helical residues 26 to 31) in the N-terminal region. In contrast to predictions by excluded-volume crowding theory, the dimer–monomer dissociation constantKDwas markedly higher in cells than in solution and dilute cell lysate. As expected, this increase was partially recapitulated under conditions of high salt concentrations, given that conserved salt bridges at the dimer interface are critically required for association. Unexpectedly, however, also the addition of the crowding agent Ficoll destabilized the dimer while the addition of bovine serum albumin (BSA) and lysozyme, often used to represent interaction with charged macromolecules, had no effect. Our results highlight the potential of DEER for in-cell study of proteins as well as the complexities of the effects of the cellular milieu on protein structures and stability.