Spotlight
Minireviews
MinireviewTaming the Beast: Interplay between Gut Small Molecules and Enteric PathogensThe overuse of antibiotics has led to the evolution of drug-resistant bacteria that are becoming increasingly dangerous to human health. According to the Centers for Disease Control and Prevention, antibiotic-resistant bacteria cause at least 2 million illnesses and 23,000 deaths in the United States annually. Traditionally, antibiotics are bactericidal or bacteriostatic agents that place selective pressure on bacteria, leading to the...
MinireviewSalmonella enterica Serovar Panama, an Understudied Serovar Responsible for Extraintestinal Salmonellosis WorldwideIn recent years nontyphoidal Salmonella has emerged as one of the pathogens most frequently isolated from the bloodstream in humans. Only a small group of Salmonella serovars cause this systemic infection, known as invasive nontyphoidal salmonellosis. Here, we present a focused minireview on Salmonella enterica serovar Panama, a serovar responsible...
Molecular Pathogenesis
Molecular PathogenesisContribution of hla Regulation by SaeR to Staphylococcus aureus USA300 PathogenesisThe SaeRS two-component system in Staphylococcus aureus is critical for regulation of many virulence genes, including hla, which encodes alpha-toxin. However, the impact of regulation of alpha-toxin by Sae on S. aureus pathogenesis has not been directly addressed. Here, we mutated the SaeR-...
Molecular PathogenesisCooperative Roles of Nitric Oxide-Metabolizing Enzymes To Counteract Nitrosative Stress in Enterohemorrhagic Escherichia coliEnterohemorrhagic Escherichia coli (EHEC) has at least three enzymes, NorV, Hmp, and Hcp, that act independently to lower the toxicity of nitric oxide (NO), a potent antimicrobial molecule. This study aimed to reveal the cooperative roles of these defensive enzymes in EHEC against nitrosative stress.
Molecular PathogenesisIdentification of an Autorepressing Two-Component Signaling System That Modulates Virulence in Streptococcus suis Serotype 2Streptococcus suis is one of the most important pathogens affecting the swine industry and is also an emerging zoonotic agent for humans. Two-component signaling systems (TCSs) play important roles in the adaptation of pathogenic bacteria to host environments. In this study, we identified a novel TCS, named TCS09HKRR, which facilitated...
Cellular Microbiology: Pathogen-Host Cell Molecular Interactions
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsHelicobacter pylori Uses the TlpB Receptor To Sense Sites of Gastric InjuryHelicobacter pylori is a pathogen that chronically colonizes the stomachs of approximately half of the world’s population and contributes to the development of gastric inflammation. We demonstrated previously in vivo that H. pylori uses motility to preferentially colonize injury sites in...
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsGroEL Protein (Heat Shock Protein 60) of Mycoplasma gallisepticum Induces Apoptosis in Host Cells by Interacting with Annexin A2Mycoplasma gallisepticum is an avian respiratory and reproductive tract pathogen that has a significant economic impact on the poultry industry worldwide. Although membrane proteins of Mycoplasma spp. are thought to play crucial roles in host interactions, very few have had their biochemical function defined. In this study, we found that the GroEL protein (...
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsStenotrophomonas maltophilia Encodes a VirB/VirD4 Type IV Secretion System That Modulates Apoptosis in Human Cells and Promotes Competition against Heterologous Bacteria, Including Pseudomonas aeruginosaStenotrophomonas maltophilia is an emerging opportunistic and nosocomial pathogen. S. maltophilia is also a risk factor for lung exacerbations in cystic fibrosis patients. S. maltophilia attaches to various mammalian cells, and we...
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsSalmonella enterica Effectors SifA, SpvB, SseF, SseJ, and SteA Contribute to Type III Secretion System 1-Independent Inflammation in a Streptomycin-Pretreated Mouse Model of ColitisSalmonella enterica serovar Typhimurium (S. Typhimurium) induces inflammatory changes in the ceca of streptomycin-pretreated mice. In this mouse model of colitis, the type III secretion system 1 (T3SS-1) has been shown to induce rapid inflammatory change in the cecum at early points, 10 to 24 h after infection. Five proteins, SipA, SopA, SopB, SopD, and SopE2...
Bacterial Infections
Bacterial InfectionsLink between Heterotrophic Carbon Fixation and Virulence in the Porcine Lung Pathogen Actinobacillus pleuropneumoniaeActinobacillus pleuropneumoniae is a capnophilic pathogen of the porcine respiratory tract lacking enzymes of the oxidative branch of the tricarboxylic acid (TCA) cycle. We previously claimed that A. pleuropneumoniae instead uses the reductive branch in order to generate energy and metabolites. Here...
Host Response and Inflammation
Host Response and InflammationParticipation of the Serine Protease Jonah66Ci in the Drosophila Antinematode Immune ResponseSerine proteases and serine protease homologs form the second largest gene family in the Drosophila melanogaster genome. Certain genes in the Jonah multigene family encoding serine proteases have been implicated in the fly antiviral immune response. Here, we report the involvement of Jonah66Ci in the Drosophila immune defense against...
Host Response and InflammationToll-Like Receptors 2 and 4 Modulate Pulmonary Inflammation and Host Factors Mediated by Outer Membrane Vesicles Derived from Acinetobacter baumanniiPneumonia due to Gram-negative bacteria is associated with high mortality. Acinetobacter baumannii is a Gram-negative bacterium that is associated with hospital-acquired and ventilator-associated pneumonia. Bacteria have been described to release outer membrane vesicles (OMVs) that are capable of mediating systemic inflammation. The mechanism by which...
Host Response and InflammationIdentification of Potential Cerebrospinal Fluid Biomarkers To Discriminate between Infection and Sterile Inflammation in a Rat Model of Staphylococcus epidermidis Catheter InfectionStaphylococcus epidermidis cerebrospinal fluid (CSF) shunt infection is a common complication of hydrocephalus treatment, creating grave neurological consequences for patients, especially when diagnosis is delayed. The current method of diagnosis relies on microbiological culture; however, awaiting culture results may cause treatment delays, or culture may fail to...
Host Response and InflammationProtective Role of Kupffer Cells and Macrophages in Klebsiella pneumoniae-Induced Liver Abscess DiseaseKlebsiella pneumoniae-induced liver abscess (KLA) is emerging as a leading cause of pyogenic liver abscess worldwide. In recent years, the emergence of hypervirulent K. pneumoniae (hvKp) has been strongly associated with KLA. Unlike classical...
Host Response and InflammationEarly Colonization of the Upper Genital Tract by Chlamydia muridarum Is Associated with Enhanced Inflammation Later in InfectionChlamydia trachomatis is the most commonly reported bacterial sexually transmitted infection in the United States. Modeling infection in animals can be challenging, as mice naturally clear C. trachomatis when it is deposited in the lower genital tract. However,...
Fungal and Parasitic Infections
Fungal and Parasitic InfectionsAnopheles gambiae Lacking AgTRIO Inefficiently Transmits Plasmodium berghei to MiceAntibodies to AgTRIO, a mosquito salivary protein, partially reduce the initial Plasmodium burden in mice. We therefore silenced AgTRIO in mosquitoes and determined the relative contribution of AgTRIO to the ability of Anopheles gambiae to transmit Plasmodium berghei to mice. RNA...
Microbial Immunity and Vaccines
Microbial Immunity and VaccinesDevelopment of Opsonic Mouse Monoclonal Antibodies against Multidrug-Resistant EnterococciMultidrug-resistant enterococci are major causes of hospital-acquired infections. Immunotherapy with monoclonal antibodies (MAbs) targeting bacterial antigens would be a valuable treatment option in this setting. Here, we describe the development of two MAbs through hybridoma technology that target antigens from the most clinically relevant enterococcal species.
Host-Associated Microbial Communities
Host-Associated Microbial Communities | SpotlightAntibiotic-Induced Shifts in Fecal Microbiota Density and Composition during Hematopoietic Stem Cell TransplantationDramatic microbiota changes and loss of commensal anaerobic bacteria are associated with adverse outcomes in hematopoietic cell transplantation (HCT) recipients. In this study, we demonstrate these dynamic changes at high resolution through daily stool sampling and assess the impact of individual antibiotics on those changes.
Author Correction
Masthead
Current Issue
About IAI
Infection and Immunity® (IAI) reports key discoveries that help microbiologists, immunologists, epidemiologists, pathologists, and clinicians to gain new insights into the underlying mechanisms of host-pathogen interactions and develop novel strategies to prevent or treat infectious diseases.