14 results match your criteria: "The University of Tokyogrid.26999.3d[Affiliation]"

The FF-ATP synthase is required for the viability of tuberculosis (TB) and nontuberculous mycobacteria (NTM) and has been validated as a drug target. Here, we present the cryo-EM structures of the Mycobacterium smegmatis F-ATPase and the FF-ATP synthase with different nucleotide occupation within the catalytic sites and visualize critical elements for latent ATP hydrolysis and efficient ATP synthesis. Mutational studies reveal that the extended C-terminal domain (αCTD) of subunit α is the main element for the self-inhibition mechanism of ATP hydrolysis for TB and NTM bacteria.

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Avian or human influenza A viruses bind preferentially to avian- or human-type sialic acid receptors, respectively, indicating that receptor tropism is an important factor for determining the viral host range. However, there are currently no reliable methods for analyzing receptor tropism biologically under physiological conditions. In this study, we established a novel system using MDCK cells with avian- or human-type sialic acid receptors and with both sialic acid receptors knocked out (KO).

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Article Synopsis
  • The global vaccination effort against COVID-19 has faced challenges due to the emergence of new virus variants that can evade immunity, necessitating the development of new therapeutic agents.
  • Research has identified a unique cell surface entry pathway for SARS-CoV-2 that operates independently of the TMPRSS2 protease and is influenced by metalloproteinase inhibitors, particularly involving the enzyme ADAM10.
  • Understanding this metalloproteinase pathway, which contributes to the virus's ability to infect cells and spread rapidly, could lead to novel treatment strategies for effectively combating COVID-19 in the future.
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Role of the Orphan Transporter SLC35E1 in the Nuclear Egress of Herpes Simplex Virus 1.

J Virol

May 2022

Division of Molecular Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyogrid.26999.3d, Tokyo, Japan.

Article Synopsis
  • - This study created a novel screening system to identify cellular proteins that interact with the herpes simplex virus 1 (HSV-1) nuclear egress complex, which is essential for the virus's exit from the nucleus of infected cells.
  • - Using advanced proteomics techniques and CRISPR/Cas9, researchers pinpointed the role of the orphan transporter SLC35E1, discovering that its knockout led to reduced HSV-1 replication and mislocalization of crucial viral proteins.
  • - The findings highlight the importance of cellular proteins in HSV-1 de-envelopment and provide a better understanding of viral processes, setting the stage for future research on viral-host interactions.
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Interorganellar cross talk is often mediated by membrane contact sites (MCSs), which are zones where participating membranes come within 30 nm of one another. MCSs have been found in organelles, including the endoplasmic reticulum, Golgi bodies, endosomes, and mitochondria. Despite its seeming ubiquity, reports of MCS involving mitochondrion-related organelles (MROs) present in a few anaerobic parasitic protozoa remain lacking.

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Hydrothermal vent ecosystems are home to a wide array of symbioses between animals and chemosynthetic microbes, among which shrimps in the genus Rimicaris is one of the most iconic. So far, studies of symbioses have been restricted to Atlantic species, including Rimicaris exoculata, which is totally reliant on the symbionts for nutrition, and the mixotrophic species Rimicaris chacei. Here, we expand this by investigating and characterizing the symbiosis of the Indian Ocean species Rimicaris kairei using specimens from two vent fields, Kairei and Edmond.

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Regardless of the general model of translation in eukaryotic cells, a number of studies suggested that many mRNAs encode multiple proteins. Leaky scanning, which supplies ribosomes to downstream open reading frames (ORFs) by readthrough of upstream ORFs, has great potential to translate polycistronic mRNAs. However, the mRNA elements controlling leaky scanning and their biological relevance have rarely been elucidated, with exceptions such as the Kozak sequence.

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Article Synopsis
  • The study investigates how the gut microbiota changes in COVID-19 patients, revealing significant differences in microbiota composition compared to healthy individuals, especially right after hospital admission.
  • Researchers found that hospitalized COVID-19 patients experienced a decrease in beneficial bacteria and an increase in pro-inflammatory bacteria, leading to ongoing dysbiosis even 21 days after illness onset.
  • The composition of gut microbiota was correlated with levels of inflammatory biomarkers, highlighting the importance of understanding these changes to better grasp the relationship between gut health and COVID-19 severity.
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The causative agents of recurrent Escherichia coli bacteremia can be genetically identical or discordant, but the differences between them remain unclear. This study aimed to explore these differences, with regard to their clinical and microbiological features. Patients were recruited from a Japanese tertiary teaching hospital based on blood culture data and the incidence of recurrent E.

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Nitrogen fixation, a distinct process incorporating the inactive atmospheric nitrogen into the active biological processes, has been a major topic in biological and geochemical studies. Currently, insights into diversity and distribution of nitrogen-fixing microbes are dependent upon homology-based analyses of nitrogenase genes, especially the gene, which are broadly conserved in nitrogen-fixing microbes. Here, we report the pitfall of using as a marker of microbial nitrogen fixation.

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Although spp. are most frequently isolated from marine environments; more rarely, they have been implicated in human infections. spp.

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Unique Gut Microbiome in HIV Patients on Antiretroviral Therapy (ART) Suggests Association with Chronic Inflammation.

Microbiol Spectr

September 2021

Division of Infectious Diseases, Advanced Clinical Research Center, the Institute of Medical Science, The University of Tokyogrid.26999.3d, Tokyo, Japan.

Chronic inflammation is a hallmark of human immunodeficiency virus (HIV) infection and a risk factor for the development and progression of age-related comorbidities. Although HIV-associated gut dysbiosis has been suggested to be involved in sustained chronic inflammation, there remains a limited understanding of the association between gut dysbiosis and chronic inflammation during HIV infection. Here, we investigated compositional changes in the gut microbiome and its role in chronic inflammation in patients infected with HIV.

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Characterized positive-strand RNA viruses replicate in association with intracellular membranes. Regarding viruses in the genus , the mechanism by which their RNA-dependent RNA polymerase (replicase) associates with membranes is understudied. Here, by membrane flotation analyses of the replicase of Plantago asiatica mosaic potexvirus (PlAMV), we identified a region in the methyltransferase (MET) domain as a membrane association determinant.

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Tigecycline is a last-resort antimicrobial against carbapenemase-producing (CPE). However, mobile tigecycline resistance genes, (X) and , have emerged in China and have spread possibly worldwide. Tet(X) family proteins function as tigecycline-inactivating enzymes, and TMexCD-TOprJ complexes function as efflux pumps for tigecycline.

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