Article
Microbiology
Tarcisio Brignoli, Edward Douglas, Seana Duggan, Olayemi Grace Fagunloye, Rajan Adhikari, M. Javad Aman, Ruth C. Masseya
Summary: The ability of Staphylococcus aureus to secrete cytolytic toxins is a major factor in its pathogenicity. This study demonstrates the role of wall teichoic acids (WTA) in the release of toxins from S. aureus cells. The presence of WTA alters the electrostatic charge of the cell envelope, thereby affecting toxin release.
MICROBIOLOGY SPECTRUM
(2022)
Article
Food Science & Technology
Wanwan Hou, Shimo Kang, Jiang Chang, Xiaorong Tian, Chunlei Shi
Summary: The study demonstrated that by inducing GlpQ to degrade WTA, LBA effectively inhibits the biofilm formation of Staphylococcus aureus, reducing its adhesive ability.
Article
Multidisciplinary Sciences
N'Toia C. Hawkins, James L. Kizziah, Asma Hatoum-Aslan, Terje Dokland
Summary: In this study, the structure of the complete virion of the Staphylococcus epidermidis-infecting phage Andhra was determined using high-resolution cryo-electron microscopy. The findings provide insights into critical features for virion assembly, host recognition, and penetration.
Article
Microbiology
Chao-Chin Liu, Mei-Hui Lin
Summary: This study demonstrates that Staphylococcus aureus relies on the presence of wall teichoic acids (WTA) and lipopolysaccharide (LPS) to hitchhike motile bacteria like Pseudomonas aeruginosa for movement. The hitchhiking motility of S. aureus is reduced when the gene encoding the WTA synthesis enzyme, TagO, is deleted, but restored when the gene is complemented. The study also shows that P. aeruginosa promotes the movement of S. aureus in the digestive system of Caenorhabditis elegans and mice.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Immunology
Breno A. B. Salgado, Elaine M. Waters, Josephine C. Moran, Aras Kadioglu, Malcolm J. Horsburgh
Summary: Staphylococcus aureus nasal colonization is a risk factor for infection, and the genetic factors promoting long-term nasal colonization are not fully understood. In this study, a murine model of nasopharyngeal colonization was used to identify genetic loci under selection. Mutations in key metabolism genes and stress response genes were identified after successive rounds of colonization. The versatility of this model allows for further studies on colonization, persistence, and evolution.
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
(2022)
Article
Genetics & Heredity
Sara M. Tamminga, Simon L. Voelpel, Kim Schipper, Thilo Stehle, Yvonne Pannekoek, Nina M. van Sorge
Summary: This study analyzed the presence and genetic variation of three WTA glycosyltransferases in the Staphylococcus aureus population. The researchers found that tarS was almost universally present in the isolates, while the co-presence of tarM and tarP were associated with specific S. aureus clonal complexes. Variations in WTA glycosylation, caused by amino acid substitutions or premature stop codons in key enzymatic residues, were found to severely affect immune recognition of the bacteria.
MICROBIAL GENOMICS
(2022)
Article
Genetics & Heredity
Sara M. Tamminga, Simon L. Voelpel, Kim Schipper, Thilo Stehle, Yvonne Pannekoek, Nina M. van Sorge
Summary: Staphylococcus aureus is a leading cause of skin and soft tissue infections and systemic infections. Wall teichoic acids (WTAs) are important for S. aureus colonization, gene transfer, and antibiotic resistance. Genetic variation of the three WTA glycosyltransferases affects immune recognition and clearance of S. aureus.
MICROBIAL GENOMICS
(2022)
Article
Biochemistry & Molecular Biology
Ronit Vogt Sionov, Shreya Banerjee, Sergei Bogomolov, Reem Smoum, Raphael Mechoulam, Doron Steinberg
Summary: This study demonstrates that the endocannabinoid Anandamide (AEA) affects multiple biochemical processes, resulting in the sensitization of drug-resistant Staphylococcus aureus to antibiotics.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Microbiology
Ting Pan, Jing Guan, Yujie Li, Baolin Sun
Summary: The study identified the LcpB protein in Staphylococcus aureus as crucial for cell wall synthesis and virulence, acting as a pyrophosphatase responsible for wall teichoic acid synthesis. Knockout of lcpB in CA-MRSA resulted in enhanced hemolytic activity and increased leukocyte infiltration, revealing a dual role of LcpB in regulating virulence in an agr-independent manner.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Environmental Sciences
Jagadish Chandra Kumar Mangu, Marios Stylianou, Per-Erik Olsson, Jana Jass
Summary: The exposure to PFAS increases susceptibility to pathogens in Caenorhabditis elegans by reducing host immunity and increasing intestinal membrane permeability, while also increasing bacterial virulence, with potential implications for humans and other animals.
ENVIRONMENTAL POLLUTION
(2022)
Article
Chemistry, Medicinal
Peng Shen, Lele Zheng, Xinfang Qin, Dan Li, Zijiang Zhang, Jie Zhao, Han Lin, Haofei Hong, Zhifang Zhou, Zhimeng Wu
Summary: In this study, glycosylated wall teichoic acids (WTAs) derived from S. aureus were modified and conjugated with tetanus toxin (TT) as potential MRSA vaccine candidates. The structure-immunogenicity relationship was evaluated in a mouse model, and the heptamer WTAs conjugate T6 showed the highest specific antibody production.
EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY
(2023)
Review
Infectious Diseases
Harshad Lade, Jae-Seok Kim
Summary: MRSA is a prevalent bacterial pathogen worldwide, and finding new antibiotic targets is crucial for successful treatment. Most antibiotics target essential biochemical processes of S. aureus, such as cell wall synthesis. Further research into novel antibiotics targeting bacterial cellular processes could lead to new therapeutic strategies against antibiotic-resistant pathogens.
Article
Immunology
Colleen S. Curran, Lindsay M. Busch, Yan Li, Cui Xizhong, Junfeng Sun, Peter Q. Eichacker, Parizad Torabi-Parizi
Summary: In this study, it was found that anti-PD-L1 therapy did not improve survival in pneumonia models in mice, suggesting the need for further preclinical studies on other common pathogens and septic foci.
JOURNAL OF INFECTIOUS DISEASES
(2021)
Article
Dermatology
Christine Youn, Dustin A. Dikeman, Evelyn Chang, Haiyun Liu, Sabrina J. Nolan, Martin P. Alphonse, Daniel P. Joyce, Qi Liu, James Meixiong, Xinzhong Dong, Lloyd S. Miller, Nathan K. Archer
Summary: Phosphodiesterase 4 (PDE4) is highly expressed in keratinocytes and immune cells, promoting pro-inflammatory responses. PDE4 inhibitors such as crisaborole have been approved for the treatment of inflammatory skin diseases, but their immunopathogenetic effects are not fully understood.
EXPERIMENTAL DERMATOLOGY
(2023)
Article
Chemistry, Medicinal
Jessica Slavetinsky, Esther Lehmann, Christoph Slavetinsky, Lisa Bleul, Rob van Dalen, Dorothee Kretschmer, Lisa Bleul, Christiane Wolz, Christopher Weidenmaier, Andreas Peschel
Summary: This study reveals that the endothelial oxidized low-density lipoprotein receptor 1 (LOX-1) interacts with Staphylococcus aureus wall teichoic acid (WTA), facilitating the binding of S. aureus to human endothelial cells. The levels of WTA and LOX-1 expression correlate with the efficacy of the S. aureus-endothelial interaction. Blocking LOX-1 may be a potential strategy for preventing or treating severe endovascular infections.
ACS INFECTIOUS DISEASES
(2023)
Article
Infectious Diseases
Martin Vestergaard, Dirk Bald, Hanne Ingmer
Summary: The ATP synthase plays a crucial role in bacteria metabolism and viability. The dependence on ATP synthase varies among different bacterial pathogens. Currently, there are approved ATP synthase inhibitors for treating tuberculosis, but no inhibitors are available for non-mycobacterial pathogens.
JOURNAL OF GLOBAL ANTIMICROBIAL RESISTANCE
(2022)
Article
Microbiology
Patricia E. Sorensen, Duncan Y. K. Ng, Luc Duchateau, Hanne Ingmer, An Garmyn, Patrick Butaye
Summary: This study investigated the impact of bacteriophages on bacterial growth dynamics and identified seven distinct growth patterns, with phage species being the most influential factor. The results highlighted the importance of phage-host dynamics in determining a phage's ability to eliminate bacteria, and suggested that phage therapy development should take into consideration these dynamics. Candidates from Group 2, characterized by high bacterial killing, were identified as the most promising for phage therapy.
Article
Genetics & Heredity
Yang Li, Kasper Mikkelsen, Oleguer Lluch i Grane, Zhenyu Wang, Yuanyue Tang, Xinan Jiao, Hanne Ingmer, Nina Molin Hoyland-Kroghsbo, Qiuchun Li
Summary: CRISPR-Cas system, especially the type III-A, plays a crucial role in protecting MRSA against foreign DNA attacks. The study shows that crRNAs closer to the leading sequence of the CRISPR array exhibit higher efficiency in directing plasmid elimination and phage resistance in MRSA.
Article
Infectious Diseases
Bolette Skive, Andreas Christian Lawaetz, Anette M. Hammerum, Henrik Hasman, Mette Pinholt, Christian Stab Jensen, Jenny Dahl Knudsen, Anne Kjerulf, Hanne Ingmer
Summary: This study investigated the survival and growth of clinical isolates of vancomycin-resistant Enterococcus faecium (VREfm) exposed to the disinfectant NaDCC Plus. The results showed that higher concentrations of NaDCC Plus could eradicate the bacteria, but shorter exposure times and longer incubation times increased the concentration needed for eradication.
JOURNAL OF GLOBAL ANTIMICROBIAL RESISTANCE
(2022)
Article
Immunology
Helene M. S. Eld, Peter R. Johnsen, Emilie M. Nielsen, Frederikke Z. Jorgensen, Marie Lindstrom-Svendsen, Mara Baldry, Hanne Ingmer, Hanne Frokiaer
Summary: This study investigated the IL-12 potentiating effect of mannan pre-treatment of bone marrow-derived dendritic cells prior to stimulation with clinical MRSA strains. It was found that mannan almost doubled IL-12 production and increased bacterial uptake and reactive oxygen species (ROS) production.
FRONTIERS IN IMMUNOLOGY
(2022)
Article
Multidisciplinary Sciences
Anaelle Faita, Yara Seif, Kasper Mikkelsen, Saugat Poudel, Jerry M. Wells, Bernhard O. Palsson, Hanne Ingmer
Summary: This study analyzed the phenotypic, mutational, and transcriptional landscape of 10 methicillin-resistant Staphylococcus aureus (MRSA) strains with decreased vancomycin susceptibility. The results showed that the mutational landscape diverged between these strains, with both previously associated mutations and novel adaptive mutations. Transcriptional analysis revealed strain-specific expression profiles and perturbed gene sets related to virulence systems. Additionally, there was a correlation between susceptibility to teichoic acid inhibitors and the variation in oxacillin susceptibility. These findings suggest that the adaptation to vancomycin involves various mutational and transcriptional pathways that affect antibiotic susceptibility and potentially impact clinical outcomes of infections.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Editorial Material
Microbiology
Dorte Frees, Hanne Ingmer
Summary: The division of bacterial cells into two daughter cells requires the coordination of multiple conserved proteins. This study identifies a novel cell division protein, SmdA, in spherical bacteria and investigates its role in cell division.
Article
Microbiology
Katrine Nohr-Meldgaard, Carsten Struve, Hanne Ingmer, Yvonne Agerso
Summary: The study examined a putative tetracycline tet(L) gene in the operational group Bacillus amyloliquefaciens and found that the risk of transfer to other non-related species is considered negligible.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Peter Riber Johnsen, Cecilia Pinna, Luce Mattio, Mathilde Bech Strube, Mattia Di Nunzio, Stefania Iametti, Sabrina Dallavalle, Andrea Pinto, Hanne Frokiaer
Summary: This study compares the effects of seven different structural types of stilbenoids on the modulation of cytokine production and antioxidant response. Monomeric compounds showed dose-dependent inhibition of cytokine production induced by E. coli, with resveratrol and piceatannol also inhibiting IL-10 production. All monomers, except trimethoxy-resveratrol, inhibited cytokine production induced by L. acidophilus. However, the dimer dehydro-delta-viniferin remarkably enhanced IL-12 production induced by L. acidophilus.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Microbiology
Malene Wollesen, Kasper Mikkelsen, Marie Selch Tvilum, Martin Vestergaard, Mikala Wang, Rikke L. Meyer, Hanne Ingmer, Thomas B. Poulsen, Thomas Torring
Summary: Polyether ionophores are complex natural products used in agriculture for their antimicrobial properties. However, their potential use in humans has been limited due to toxicity concerns. In this study, we found distinct differences among different polyether ionophores in their effects on Staphylococcus aureus, both in standard assays and in more complex systems. This provides valuable information for future investigations and optimization of these compounds.
MICROBIOLOGY SPECTRUM
(2023)
Article
Biochemistry & Molecular Biology
Anaelle Fait, Dan I. Andersson, Hanne Ingmer
Summary: The loss of resistance in vancomycin-intermediate Staphylococcus aureus (VISA) strains is correlated with an increase in fitness and is attributed to adaptive mutations. Upon re-exposure to vancomycin, these revertants evolve faster and reach higher levels of resistance than vancomycin-naive cells. This suggests that previous vancomycin adaptation should be considered a risk factor when deciding on antimicrobial chemotherapy.
Article
Veterinary Sciences
Marie Sijp Just, Bolette Skive, Hanne Ingmer, Vibeke Mogelmose, Lene Lund Lindegaaard, Lis Alban
Summary: This study assesses the Salmonella exposure risk to consumers from bile-contaminated pig carcasses. The research found no Salmonella in 300 bile samples. The simulation model showed that the risk of consumers being exposed to Salmonella through bile-contaminated carcasses is negligible.
PREVENTIVE VETERINARY MEDICINE
(2023)
Article
Cell Biology
Jingxian Yang, Janine Zara Bowring, Janes Krusche, Esther Lehmann, Tom Grunert, Benjamin Svejdal Bejder, Stephanie Fulaz Silva, Martin Saxtorph Bojer, Andreas Peschel, Hanne Ingmer
Summary: Bacteria use quorum sensing to coordinate group behavior, and some phages also respond to quorum sensing. These interactions likely impact bacterial group behavior, microbial ecology, and the efficacy of phage therapies.
Article
Microbiology
Kasper Mikkelsen, Janine Zara Bowring, Yong Kai Ng, Frida Svanberg Frisinger, Julie Kjaersgaard Maglegaard, Qiuchun Li, Raphael N. Sieber, Andreas Petersen, Paal Skytt Andersen, Jakob T. Rostol, Nina Molin Hoyland-Kroghsbo, Hanne Ingmer
Summary: CRISPR-Cas is an adaptive immune system that protects bacteria and archaea against mobile genetic elements such as phages. In strains of Staphylococcus aureus, CRISPR-Cas is rare but when present, it is located within the SCCmec element, which encodes resistance to methicillin and other β-lactam antibiotics.
MICROBIOLOGY SPECTRUM
(2023)
Article
Microbiology
Janine Zara Bowring, Yue Su, Ahlam Alsaadi, Sine L. Svenningsen, Julian Parkhill, Hanne Ingmer
Summary: Bacteriophage-mediated transduction is a major mechanism for horizontal gene transfer in bacterial pathogens, and understanding this process is crucial for combating virulence and antibiotic resistance.
MICROBIOLOGY SPECTRUM
(2022)