Article
Immunology
Jin-Li Ding, Kang Wei, Ming-Guang Feng, Sheng-Hua Ying
Summary: In this study, researchers identified and functionally characterized five enterotoxin_A domain proteins in filamentous fungus B. bassiana. These proteins play important roles in stress response, development, and virulence. The loss of these proteins leads to reduced conidial production and increased sensitivity to oxidative and cell wall-perturbing stresses. Additionally, the loss of these proteins causes changes in the carbohydrate profiles of the fungal cell surface, which enhance host immune reactions.
FRONTIERS IN IMMUNOLOGY
(2023)
Article
Microbiology
Chang Liu, Hua Zhang, Xian Peng, Meghan S. Blackledge, Robert E. Furlani, Haoting Li, Zhaoming Su, Roberta J. Melander, Christian Melander, Suzanne Michalek, Hui Wu
Summary: Antibiotic resistance is a major concern in public health, and new alternatives to combat biofilm-driven infections are needed. A 2-aminoimidazole derivative has been identified to inhibit biofilm formation in Streptococcus mutans and Staphylococcus aureus by targeting a key transcriptional regulator. This compound shows promise as a new anti-infective agent that can attenuate virulence in bacterial infections.
Article
Plant Sciences
Katherine E. Helliwell, Friedrich H. Kleiner, Hayley Hardstaff, Abdul Chrachri, Trupti Gaikwad, Deborah Salmon, Nicholas Smirnoff, Glen L. Wheeler, Colin Brownlee
Summary: Diatoms are globally important phytoplankton that dominate coastal and polar-ice assemblages. They employ Ca2+ signaling to respond to osmotic stress and regulate cell volume.
Article
Veterinary Sciences
Dongjie Sun, Yufu Liu, Xiaowei Peng, Hao Dong, Hui Jiang, Xuezheng Fan, Yu Feng, Jiali Sun, Kun Han, Qiang Gao, Jianrui Niu, Jiabo Ding
Summary: The process of intracellular proteolysis via ATP-dependent proteases is biologically conserved. The ATP-dependent Clp protease is associated with stress responses and bacterial virulence in various pathogenic bacteria. A Brucella abortus 2308 strain with a ?clpP mutation was constructed to investigate the function of ClpP peptidase. The results revealed that the ?clpP mutant strain exhibited impaired growth in TSB medium and increased sensitivity to various stress conditions. Additionally, deletion of clpP significantly affected Brucella virulence and led to perturbations in gene and protein expression related to energy production, cell wall/membrane/envelope biogenesis, carbohydrate transport, and metabolism.
VETERINARY RESEARCH
(2023)
Article
Cell Biology
Kin Ki Jim, Rieza Aprianto, Rutger Koning, Arnau Domenech, Jun Kurushima, Diederik van de Beek, Christina M. J. E. Vandenbroucke-Grauls, Wilbert Bitter, Jan-Willem Veening
Summary: This study investigates the specific transcriptional responses of pneumolysin and identifies key pathways involved in early pneumococcal meningitis using an in vivo dual RNA sequencing approach. The study provides new insights into the interactions between the host and pathogen during the early phase of central nervous system infection.
Review
Biochemistry & Molecular Biology
Perumalraja Kirthika, Khristine Kaith Sison Lloren, Vijayakumar Jawalagatti, John Hwa Lee
Summary: Proteases are essential enzymes that carry out proteolysis in all living organisms and play a crucial role in cell survival. Lon protease, as a global regulator in bacteria, governs various important functions and pathways, including DNA replication and repair, stress response, and biofilm formation. Understanding the contribution and mechanisms of Lon in bacterial pathogenesis is therefore crucial. In this review, we discuss the structure and substrate specificity of bacterial Lon protease, as well as its ability to regulate bacterial pathogenesis.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Multidisciplinary Sciences
Benjamin Rothe, Simon Fortier, Celine Gagnieux, Celine Schmuziger, Daniel B. Constam
Summary: This study reveals a new mechanism for the regulation of mRNA transition by the protein Bicaudal-C (Bicc1). The dispersion and condensation of Bicc1 granules are controlled by the proteins ANKS3 and ANKS6, which subsequently affect the immobilization of client mRNAs.
Article
Food Science & Technology
Rajashri Banerji, Astha Karkee, Poonam Kanojiya, Amrita Patil, Sunil D. Saroj
Summary: Listeria monocytogenes encounters various stresses and polymicrobial communities during transmission, utilizing regulatory mechanisms such as quorum sensing for gene expression. The quorum-sensing system of L. monocytogenes shares homologs across genus and domain, potentially responding to signals from other bacteria and hosts. Understanding bacterial communication and stress response interactions can aid in developing food processing technologies and therapeutics.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Wentao Kong, Yuanchao Qian, Philip S. Stewart, Ting Lu
Summary: Synthetic biology has demonstrated the potential to program living microorganisms for various applications. However, current engineering practices mainly focus on planktonic cells, while microbes in nature constantly alternate their lifestyles. This study presents a synthetic genetic program that regulates bacterial life cycle and enables phase-specific gene expression. The program utilizes an engineered protein as the biofilm matrix building block and allows controlled biofilm assembly and decomposition as well as responsive planktonic-biofilm phase transition. By coupling with synthesis modules, it can be programmed for various functional realizations. This work establishes a versatile platform for microbial engineering and gene circuit applications in complex environments.
NATURE CHEMICAL BIOLOGY
(2023)
Article
Microbiology
Christopher W. Hamm, Daxton R. Butler, Matthew T. Cabeen
Summary: Bacterial survival depends on appropriate responses to diverse stressors. The environmental model bacterium Bacillus subtilis uses stressosomes to sense environmental stressors and enact the general stress response. Different RsbR paralogs show distinct response magnitude and timing, and can distinguish among stressors.
Article
Multidisciplinary Sciences
Sebastian Hendrix, Jenina Kingma, Roelof Ottenhoff, Masoud Valiloo, Monika Svecla, Lobke F. Zijlstra, Vinay Sachdev, Kristina Kovac, Johannes H. M. Levels, Aldo Jongejan, Jan F. de Boer, Folkert Kuipers, Antoine Rimbert, Giuseppe D. Norata, Anke Loregger, Noam Zelcer
Summary: SPRING is identified as a post-transcriptional regulator of SREBP activation, controlling cholesterol and fatty acid metabolism. Liver-specific knockout of Spring results in attenuated SREBP signaling, decreased plasma cholesterol, and reduced hepatic lipid content in mice. SPRING gene variants are also associated with levels of circulating HDL cholesterol and ApoA1 in humans. This study highlights the importance of SPRING in hepatic SREBP signaling and systemic lipid metabolism in both mice and humans.
NATURE COMMUNICATIONS
(2023)
Article
Cell & Tissue Engineering
Shani Ben-Moshe, Tamar Veg, Rita Manco, Stav Dan, Delfina Papinutti, Aviezer Lifshitz, Aleksandra A. Kolodziejczyk, Keren Bahar Halpern, Eran Elinav, Shalev Itzkovitz
Summary: The liver has the ability to rapidly regenerate after acute damage. In this study, single-cell RNA sequencing was used to investigate the dynamics of mouse liver regeneration after acetaminophen intoxication, revealing different mechanisms involved in hepatocyte proliferation, reprogramming, and immune recruitment.
Article
Food Science & Technology
Christos Toliopoulos, Efstathios Giaouris
Summary: Listeria monocytogenes is a foodborne pathogen that can form biofilms on various surfaces and express different genes in biofilm and planktonic cells, which could affect its stress tolerance and virulence. This study investigated the expression of ten key stress response and/or virulence-related genes in three different strains of L. monocytogenes and found strain-dependent differential gene expression between biofilm and planktonic cells, suggesting the importance of considering strain variability in studies and eradication methods of pathogenic biofilms.
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
(2023)
Article
Microbiology
Chao-Tsai Liao, Chih-En Li, Hsiao-Ching Chang, Chien-Hui Hsu, Ying-Chuan Chiang, Yi-Min Hsiao
Summary: This study provides the first functional understanding of LolB in Xanthomonas and offers new insights into the function of LolB in bacteria.
Article
Biochemistry & Molecular Biology
Rodrigo H. Coronel-Tellez, Mateusz Pospiech, Maxime Barrault, Wenfeng Liu, Valerie Bordeau, Christelle Vasnier, Brice Felden, Bruno Sargueil, Philippe Bouloc
Summary: Staphylococcus aureus adjusts its metabolism to cope with iron deprivation within the host, and the small non-coding RNA IsrR plays an important role in this process. IsrR down-regulates the translation of enzymes involved in anaerobic nitrate respiration during iron starvation. Additionally, IsrR is required for the full lethality of S. aureus in a mouse septicemia model.
NUCLEIC ACIDS RESEARCH
(2022)
Article
Biochemical Research Methods
Shiny B. Martis, Michel Droux, Florelle Deboudard, William Nasser, Sam Meyer, Sylvie Reverchon
Summary: A rapid and sensitive HPLC method with photometric and fluorescence detection has been developed for routine analysis of the catabolite product KDG from pectin and alginate. The method is simple, highly sensitive, and accurate, suitable for time course analysis of pectin or alginate degradation.
ANALYTICAL BIOCHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Sylvie Reverchon, Sam Meyer, Raphael Forquet, Florence Hommais, Georgi Muskhelishvili, William Nasser
Summary: The study reveals the importance of IHF heterodimeric protein in bacterial adaptation and pathogenicity, as its absence affects the transcriptional organization and virulence gene expression of the bacteria.
NUCLEIC ACIDS RESEARCH
(2021)
Review
Microbiology
Julie Baltenneck, Sylvie Reverchon, Florence Hommais
Summary: Quorum sensing is a mechanism by which bacterial populations coordinate gene expression through chemical communication, commonly used by pathogens to control virulence factor and environmental adaptation gene expression. Several quorum sensing mechanisms have been identified in phytopathogenic bacteria, utilizing different signal molecules. Research focuses on major phytopathogenic bacteria and their quorum sensing systems.
Article
Microbiology
Raphael Forquet, Maiwenn Pineau, William Nasser, Sylvie Reverchon, Sam Meyer
Summary: This study focuses on the role of the discriminator as a global sensor of supercoiling variations and proposes the first quantitative regulatory model based on the specific step of promoter opening during transcription initiation. It identifies a significant determinant of promoter supercoiling sensitivity and underpins the ubiquitous regulatory action of DNA supercoiling on the core transcriptional machinery in response to quick environmental changes, across a wide range of species as confirmed by extensive global high-throughput expression data analysis.
Article
Microbiology
Nicole Hugouvieux-Cotte-Pattat, Monique Royer, Erwan Gueguen, Paul Le Guen, Roderich D. Suessmuth, Sylvie Reverchon, Stephane Cociancich
Summary: The Vfm quorum sensing system is important for the virulence of Dickeya bacteria, with a strain-specific polymorphism in the biosynthesis genes vfmO and vfmP potentially leading to the production of different analogues of the QS signal.
ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Shiny B. Martis, Michel Droux, William Nasser, Sylvie Reverchon, Sam Meyer
Summary: This study discovered that the dynamic expression of pectate lyases in Dickeya dadantii is controlled by a metabolic switch involving glucose and pectin. The researchers measured the concentration profiles of key metabolites and developed a dynamic model to explain the process. The model showed that the activity of pelE and pelD genes is regulated by a mechanism of carbon catabolite repression, directly affecting the virulence of D. dadantii.
JOURNAL OF BIOLOGICAL CHEMISTRY
(2022)
Article
Microbiology
Raphael Forquet, Xuejiao Jiang, William Nasser, Florence Hommais, Sylvie Reverchon, Sam Meyer
Summary: This study presents the first transcriptomic map of a Dickeya species, which can significantly contribute to the field of phytopathogenicity. It also demonstrates the application of long-read Nanopore native RNA-seq in prokaryotes. The findings provide insights into the coordination of transcription in bacteria and suggest that gene expression is controlled at the level of transcription units rather than operons. The results have implications for microbial research and challenge the traditional operon model.
Review
Microbiology
Diana Le Berre, Sylvie Reverchon, Georgi Muskhelishvili, William Nasser
Summary: This article discusses the relationship between the dynamics of chromosome structural changes and the regulation of gene expression during bacterial adaptation. Research has shown that in the context of living cells, transcriptional regulation is more complex than what is described by in vitro biochemical studies, including the subcellular localization of molecules and the dynamics of chromosome structure. However, the dynamic reorganization of chromosomes under changing environmental conditions and its relationship with gene expression are still unclear.
Article
Biochemistry & Molecular Biology
Raphael Forquet, William Nasser, Sylvie Reverchon, Sam Meyer
Summary: DNA supercoiling acts as a global transcriptional regulator in bacteria. A thermodynamic model based on DNA elasticity is developed to predict the relative activation of promoters with different spacer lengths. The model is validated through in vitro and in vivo expression assays and genome-scale analysis in Escherichia coli, demonstrating the significant effect of spacer length on genomic expression after superhelical variations.
NUCLEIC ACIDS RESEARCH
(2022)
Article
Biochemistry & Molecular Biology
Maiwenn Pineau, Shiny B. Martis, Raphael Forquet, Jessica Baude, Camille Villard, Lucie Grand, Florence Popowycz, Laurent Soulere, Florence Hommais, William Nasser, Sylvie Reverchon, Sam Meyer
Summary: DNA supercoiling is a crucial mechanism in bacterial chromosome compaction, which is regulated by specific topoisomerases, physiological conditions, and genomic context. The altered supercoiling level leads to changes in global gene expression in bacteria.
NUCLEIC ACIDS RESEARCH
(2022)