antibiotic resistance
Bacterial InfectionsAnimal Model To Study Klebsiella pneumoniae Gastrointestinal Colonization and Host-to-Host TransmissionAn important yet poorly understood facet of the life cycle of a successful pathogen is host-to-host transmission. Hospital-acquired infections (HAI) resulting from the transmission of drug-resistant pathogens affect hundreds of millions of patients worldwide. Klebsiella pneumoniae, a Gram-negative bacterium, is notorious for causing HAI, with many of these infections...
Host-Associated Microbial CommunitiesA Role of Epithelial Cells and Virulence Factors in Biofilm Formation by Streptococcus pyogenes In VitroBiofilm formation by Streptococcus pyogenes (group A streptococcus [GAS]) in model systems mimicking the respiratory tract is poorly documented. Most studies have been conducted on abiotic surfaces, which poorly represent human tissues. We have previously shown that GAS forms mature and antibiotic-resistant biofilms on physiologically relevant epithelial cells....
Minireview | SpotlightThe Great ESKAPE: Exploring the Crossroads of Bile and Antibiotic Resistance in Bacterial PathogensThroughout the course of infection, many pathogens encounter bactericidal conditions that threaten the viability of the bacteria and impede the establishment of infection. Bile is one of the most innately bactericidal compounds present in humans, functioning to reduce the bacterial burden in the gastrointestinal tract while also aiding in digestion. It is becoming increasingly apparent that pathogens successfully resist the bactericidal...
MinireviewFitness Trade-Offs Resulting from Bacteriophage Resistance Potentiate Synergistic Antibacterial StrategiesBacteria that cause life-threatening infections in humans are becoming increasingly difficult to treat. In some instances, this is due to intrinsic and acquired antibiotic resistance, indicating that new therapeutic approaches are needed to combat bacterial pathogens. There is renewed interest in utilizing viruses of bacteria known as bacteriophages (phages) as potential antibacterial therapeutics. However, critics suggest that similar...
MinireviewOuter Membrane Lipid Secretion and the Innate Immune Response to Gram-Negative BacteriaThe outer membrane (OM) of Gram-negative bacteria is an asymmetric lipid bilayer that consists of inner leaflet phospholipids and outer leaflet lipopolysaccharides (LPS). The asymmetric character and unique biochemistry of LPS molecules contribute to the OM’s ability to function as a molecular permeability barrier that protects the bacterium against hazards in the environment. Assembly and regulation of the OM have been extensively...
Bacterial InfectionsAntibiotic Degradation by Commensal Microbes Shields PathogensThe complex bacterial populations that constitute the gut microbiota can harbor antibiotic resistance genes (ARGs), including those encoding β-lactamase enzymes (BLA), which degrade commonly prescribed antibiotics such as ampicillin. The prevalence of such genes in commensal bacteria has been increased in recent years by the wide use of antibiotics in human populations and in livestock. While transfer of ARGs between bacterial species...
Bacterial InfectionsKlebsiella pneumoniae Expressing VIM-1 Metallo-β-Lactamase Is Resensitized to Cefotaxime via Thiol-Mediated Zinc ChelationAntibiotic-resistant Klebsiella pneumoniae isolates constitute a great clinical challenge. One important resistance mechanism in K. pneumoniae is the metallo-β-lactamases (MBLs), which require zinc for their function. Thus, zinc chelation could be a strategy to resensitize...
Host-Associated Microbial Communities | SpotlightBacteriophage Resistance Alters Antibiotic-Mediated Intestinal Expansion of EnterococciEnterococcus faecalis is a human intestinal pathobiont with intrinsic and acquired resistance to many antibiotics, including vancomycin. Nature provides a diverse and virtually untapped repertoire of bacterial viruses, or bacteriophages (phages), that could be harnessed to combat multidrug-resistant enterococcal infections.
Bacterial InfectionsH2S, a Bacterial Defense Mechanism against the Host Immune ResponseThe biological mediator hydrogen sulfide (H2S) is produced by bacteria and has been shown to be cytoprotective against oxidative stress and to increase the sensitivity of various bacteria to a range of antibiotic drugs. Here we evaluated whether bacterial H2S provides resistance against the immune response, using two bacterial species that are common sources of nosocomial infections,...
Host-Associated Microbial CommunitiesCeftriaxone Administration Disrupts Intestinal Homeostasis, Mediating Noninflammatory Proliferation and Dissemination of Commensal EnterococciEnterococci are Gram-positive commensals of the mammalian intestinal tract and harbor intrinsic resistance to broad-spectrum cephalosporins. Disruption of colonization resistance in humans by antibiotics allows enterococci to proliferate in the gut and cause disseminated infections.