Host-Microbe Biology
Observation | Host-Microbe BiologyType IV Pili Can Mediate Bacterial Motility within Epithelial CellsHost cell invasion can contribute to disease pathogenesis by the opportunistic pathogen Pseudomonas aeruginosa. Previously, we showed that the type III secretion system (T3SS) of invasive P. aeruginosa strains modulates cell entry and subsequent escape from vacuolar trafficking to host lysosomes....
Editor's Pick Research Article | Host-Microbe BiologyPathogenic Escherichia coli Hijacks GTPase-Activated p21-Activated Kinase for Actin Pedestal FormationEnteropathogenic E. coli and enterohemorrhagic E. coli (EPEC and EHEC, respectively) remain a significant global health problem. Both EPEC and EHEC initiate infection by attaching to cells in the host intestine, triggering the formation of actin-rich “pedestal” structures directly beneath the...
Research Article | Host-Microbe BiologyIdentification of the Cell-Surface Protease ADAM9 as an Entry Factor for Encephalomyocarditis VirusEMCV is an animal pathogen that causes acute viral infections, usually myocarditis or encephalitis. It is thought to circulate mainly among rodents, from which it is occasionally transmitted to other animal species, including humans. EMCV causes fatal outbreaks of myocarditis and encephalitis in pig farms and zoos, making it an important veterinary pathogen. Although EMCV has been widely used as a model to study mechanisms of viral...
Editor's Pick Research Article | Host-Microbe BiologyA Protein Antagonist of Activation-Induced Cytidine Deaminase Encoded by a Complex Mouse RetrovirusComplex retroviruses, such as human immunodeficiency virus type 1 (HIV-1), cause many human deaths. These retroviruses produce lifelong infections through viral proteins that interfere with host immunity. The complex retrovirus mouse mammary tumor virus (MMTV) allows for studies of host-pathogen interactions not possible in humans. A mutation preventing expression of the MMTV Rem protein in two different MMTV strains decreased proviral...
Research Article | Host-Microbe BiologyThe Cervicovaginal Microbiota-Host Interaction Modulates Chlamydia trachomatis InfectionThe vaginal microbiota is believed to protect women against Chlamydia trachomatis, the etiologic agent of the most prevalent sexually transmitted infection (STI) in developed countries. The mechanism underlying this protection has remained elusive. Here, we reveal the comprehensive strategy by which the cervicovaginal microbiota modulates host functions to protect...
Research Article | Host-Microbe BiologyGamma Interferon Alters Junctional Integrity via Rho Kinase, Resulting in Blood-Brain Barrier Leakage in Experimental Viral EncephalitisIn an experimental viral encephalitis mouse model in which mice are infected with reovirus, we show that IFN-γ induces blood-brain barrier leakage. We show that IFN-γ promotes Rho kinase activity, resulting in actin cytoskeletal contractions in the brain endothelium that lead to vascular junctional disorganization and cell-cell separations. These studies now provide insight into a previously unknown mechanism for how blood-brain barrier...
Research Article | Host-Microbe BiologyTransposon Mutagenesis in Chlamydia trachomatis Identifies CT339 as a ComEC Homolog Important for DNA Uptake and Lateral Gene TransferChlamydia trachomatis infections have an immense impact on public health; however, understanding the basic biology and pathogenesis of this organism has been stalled by the limited repertoire of genetic tools. This report describes the successful adaptation of an important tool that has been lacking in Chlamydia studies: transposon mutagenesis. This advance...
Research Article | Host-Microbe BiologyA Chaperone for the Stator Units of a Bacterial FlagellumThe bacterial flagellum is a reversible rotating motor powered by ion transport through stator units, which also exert torque on the rotor component to turn the flagellum for motility. Species-specific adaptations to flagellar motors impact stator function to meet the demands of each species to sufficiently power flagellar rotation. We identified another evolutionary adaptation by discovering that FlgX of...
Research Article | Host-Microbe BiologyDisruption of Glycolysis by Nutritional Immunity Activates a Two-Component System That Coordinates a Metabolic and Antihost Response by Staphylococcus aureusTwo-component regulatory systems enable bacteria to adapt to changes in their environment during infection by altering gene expression and coordinating antihost responses. Despite the critical role of two-component systems in bacterial survival and pathogenesis, the activating signals for most of these regulators remain unidentified. This is exemplified by ArlRS, a ...
Research Article | Host-Microbe BiologyAnopheles Salivary Gland Architecture Shapes Plasmodium Sporozoite Availability for TransmissionMalaria continues to have a devastating impact on human health. With growing resistance to insecticides and antimalarial drugs, as well as climate change predictions indicating expansion of vector territories, the impact of malaria is likely to increase. Additional insights regarding pathogen migration through vector mosquitoes are needed to develop novel methods to prevent transmission to new hosts. Pathogens, including the microbes...