Article
Immunology
Serena Li-Sue Yan, Il-Young Hwang, Olena Kamenyeva, Juraj Kabat, Ji Sung Kim, Chung Park, John H. Kehrl
Summary: This study demonstrates the critical role of RGS protein/G alpha(i) interactions in shaping neutrophil responses to chemoattractant receptor activation. Mutant neutrophils with disabled RGS protein-G alpha(i2) interactions show impaired trafficking and inflammatory responses, providing insights into the importance of these interactions in normal neutrophil function.
FRONTIERS IN IMMUNOLOGY
(2021)
Article
Multidisciplinary Sciences
Korbinian Kienle, Katharina M. Glaser, Sarah Eickhoff, Michael Mihlan, Konrad Knoepper, Eduardo Reategui, Maximilian W. Epple, Matthias Gunzer, Ralf Baumeister, Teresa K. Tarrant, Ronald N. Germain, Daniel Irimia, Wolfgang Kastenmueller, Tim Laemmermann
Summary: The study found that neutrophils have evolved an intrinsic mechanism to limit self-aggregation during inflammation, with GPCR desensitization acting as a negative feedback control to stop migration when high concentrations of attractants are detected. However, interfering with this process may hinder bacterial clearance, as bacteria proliferation within neutrophil clusters becomes impeded. This highlights the delicate balance of neutrophil chemotaxis and arrest in combating bacterial escape.
Review
Biochemistry & Molecular Biology
Julianne M. Thornton, Kingsley Yin
Summary: Host response to bacterial infection involves leukocyte activation, inflammatory mediator release, phagocytosis, and killing of bacteria, while resolution of infection requires attenuation of neutrophil migration, neutrophil apoptosis, and other processes. Specialized Pro-resolving Mediators (SPMs) are bioactive fatty acids that play a critical role in promoting the resolution of infectious inflammation and bacterial clearance, including a novel mechanism of reducing bacterial virulence.
Article
Cell Biology
Maxime Galloy, Catherine Lachance, Xue Cheng, Felix Distefano-Gagne, Jacques Cote, Amelie Fradet-Turcotte
Summary: This article introduces experimental methods for studying the key mechanisms of chromatin modification, such as purifying native chromatin modifier complexes and producing recombinant nucleosomes. In addition, a new approach is proposed to study the functions of essential chromatin modifiers by inducing their quick depletion from the nucleus.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Article
Biochemistry & Molecular Biology
Nathan P. Bullen, David Sychantha, Stephanie S. Thang, Peter H. Culviner, Marta Rudzite, Shehryar Ahmad, Vraj S. Shah, Alain Filloux, Gerd Prehna, John C. Whitney
Summary: ADP-ribosyltransferases (ARTs) are bacterial virulence factors that modify essential proteins to promote pathogenesis. This study reports the discovery of RhsP2 as an ART toxin delivered by a type VI secretion system. RhsP2 can ADP-ribosylate double-stranded RNA, leading to inhibition of translation and disruption of tRNA processing, ultimately causing cell death. This finding uncovers a previously unknown mechanism of bacterial antagonism and highlights the unprecedented activity of ART enzymes.
Review
Food Science & Technology
Maria Elisa Caetano-Silva, Flavia Maria Netto, Maria Teresa Bertoldo-Pacheco, Amparo Alegria, Antonio Cilla
Summary: Bioactive peptides derived from food proteins have various bioactivities, including metal-binding capacity. Mineral chelating peptides have the potential to reduce mineral deficiencies and pro-oxidant effects of Fe.
CRITICAL REVIEWS IN FOOD SCIENCE AND NUTRITION
(2021)
Article
Microbiology
C. Keith Cassidy, Zhuan Qin, Thomas Frosio, Khoosheh Gosink, Zhengyi Yang, Mark S. P. Sansom, Phillip J. Stansfeld, John S. Parkinson, Peijun Zhang
Summary: In this study, the researchers investigated the structure of the core signaling units (CSUs) in the chemotaxis pathway of motile bacteria using cryo-electron tomography. They also predicted the atomic structures and protein-protein interfaces of the CSU's constituent proteins. Molecular dynamics simulations provided new insights into the periplasmic organization of the complex and previously unresolved interactions between individual CheA domains. This study enhances our understanding of the structural mechanisms underlying chemotaxis signaling and regulation.
Article
Microbiology
Marissa A. Berry, Ekaterina P. Andrianova, Igor B. Zhulin
Summary: Chemosensory systems in bacteria and archaea are complex and multi-protein pathways that allow rapid cellular response to environmental changes. CheA histidine kinase, a central component of these systems, lacks a sensor domain and relies on dedicated chemoreceptors for sensing. This study provides a genomic survey of CheA domain composition from thousands of bacteria and archaea, revealing variations and deviations from the canonical architecture. It lays the foundation for better classification of CheA homologs and identifies targets for experimental investigations.
MICROBIOLOGY SPECTRUM
(2023)
Article
Agricultural Engineering
Yu -Xi Gao, Xing Li, Xiao-Yan Fan, Jun-Ru Zhao, Zhong-Xing Zhang
Summary: This study investigated the effects of copper on antibiotic resistance genes and bacterial/archaeal community in activated sludge. The results showed that copper concentrations influenced the distribution and transmission of resistance genes, with bacteria being the main hosts for specific genes.
BIORESOURCE TECHNOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Brittany A. Fleming, Matthew G. Blango, Alexis A. Rousek, William M. Kincannon, Alexander Tran, Adam J. Lewis, Colin W. Russell, Qin Zhou, Lisa M. Baird, Amelia E. Barber, John R. Brannon, Connor J. Beebout, Vahe Bandarian, Maria Hadjifrangiskou, Michael T. Howard, Matthew A. Mulvey
Summary: This article investigates the impact of tRNA modifications on bacterial adaptation to environmental changes. The study reveals that bacteria can regulate the modification status of tRNA by adjusting the levels of the tRNA modifying enzyme MiaA, which in turn affects bacterial fitness and virulence. These findings uncover a rapid regulatory mechanism employed by bacteria in response to environmental shifts.
NUCLEIC ACIDS RESEARCH
(2022)
Article
Multidisciplinary Sciences
Mar Perez-Ruiz, Mar Pulido-Cid, Juan Roman Luque-Ortega, Jose Maria Valpuesta, Ana Cuervo, Jose L. Carrascosa
Summary: The passage of viral DNA in bacteriophage T7 involves the assembly of core proteins gp15 and gp16 into a tube structure within the periplasm, allowing DNA transfer. The interaction between these proteins results in the formation of a channel for DNA translocation and also involves a transglycosylase motif for peptidoglycan layer degradation. This complex matches the structure of the phage tail and proposes a model for the assembly of the core translocation complex, elucidating the molecular mechanism of T7 viral DNA release into the bacterial cytoplasm.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Toxicology
Churaibhon Wisessaowapak, Piyajit Watcharasit, Jutamaad Satayavivad
Summary: Arsenic impairs neuronal insulin signaling by reducing IR autophosphorylation, increasing free PI3K-p85 levels, and inhibiting PI3K activity.
TOXICOLOGY LETTERS
(2021)
Article
Multidisciplinary Sciences
Marie-Claire Daugeron, Sophia Missoury, Violette Da Cunha, Noureddine Lazar, Bruno Collinet, Herman van Tilbeurgh, Tamara Basta
Summary: The synthesis of t(6)A, a universal tRNA modification, is catalyzed by the KEOPS complex in Archaea and Eukaryotes. A fifth subunit, Gon7, is found only in Fungi and Metazoa. In this study, a fifth KEOPS subunit, Pcc2, is identified in Archaea and it is structurally and functionally similar to eukaryotic Gon7. Pcc2 regulates the oligomeric state of the KEOPS complex, which is conserved from Archaea to Eukaryotes.
NATURE COMMUNICATIONS
(2023)
Article
Genetics & Heredity
Gaurav Dugar, Andreas Hofmann, Dieter W. Heermann, Leendert W. Hamoen
Summary: A study reveals the existence of large nucleoprotein complexes formed by the transcription factor Rok in the bacterium Bacillus subtilis. These complexes can interact with each other over long distances and lead to the formation of chromosomal loops, spatially isolating large sections of DNA.
Article
Biochemistry & Molecular Biology
Armelle Vigouroux, Thibault Meyer, Anais Naretto, Pierre Legrand, Magali Aumont-Nicaise, Aurelie Di Cicco, Sebastien Renoud, Jeanne Dore, Daniel Levy, Ludovic Vial, Celine Lavire, Solange Morera
Summary: The species-specific region SpG8-1b plays a critical role in controlling the transition between rhizospheric and pathogenic lifestyles of the plant pathogen. The transcriptional regulator Atu1419, belonging to the VanR group of GntR superfamily, represses genes in the HCAs catabolic pathway and is regulated by the effector molecule N5,N10-methylenetetrahydrofolate. The study sheds light on the allosteric mechanism of transcription employed by this GntR repressor.
NUCLEIC ACIDS RESEARCH
(2021)