Gram-negative bacteria
Research Article | Clinical Science and EpidemiologyClinical and Molecular Description of a High-Copy IncQ1 KPC-2 Plasmid Harbored by the International ST15 Klebsiella pneumoniae CloneIn many parts of the world, carbapenem resistance is a serious public health concern. In Brazil, carbapenem resistance in Enterobacterales is mostly driven by the dissemination of KPC-2-producing K. pneumoniae clones. Despite being endemic in this country, only a few reports providing both clinical and genomic data are available in Brazil, which limit the...
Research Article | Host-Microbe BiologyDevelopment of a Plasmid Shuttle Vector System for Genetic Manipulation of Chlamydia psittaciPsittacosis, caused by avian C. psittaci, has a major economic impact in the poultry industry worldwide and represents a significant risk for zoonotic transmission to humans. In the past decade, the tools of genetic manipulation have been improved for chlamydial molecular studies. While several genetic tools have been mainly developed in...
Research Article | Clinical Science and EpidemiologyA Cohort Study of the Impact of Carbapenem-Resistant Enterobacteriaceae Infections on Mortality of Patients Presenting with SepsisThe importance of this work relies on exploring the impact of multidrug-resistant bacterial infections such as those with carbapenem-resistant Enterobacteriaceae (CRE) on sepsis mortality. These infections are growing at alarming rates worldwide and are now among the most frequent and difficult-to-treat bacteria due to the very few options for susceptible antimicrobials available. This study examined 1,190 sepsis episodes, and...
Research Article | Applied and Environmental ScienceConjugative Selectivity of Plasmids Is Affected by Coexisting Recipient CandidatesMost previous studies on plasmid conjugal transfer employed experimental setups with two strains: one as a donor and the other as a recipient. However, the results obtained sometimes failed to agree with observations obtained under natural environmental conditions or in a model microcosm using natural soil and water samples. Therefore, we consider that there is a “gap” in our understanding of plasmid behavior in the context of bacterial...
Research Article | Therapeutics and PreventionVitamin E Increases Antimicrobial Sensitivity by Inhibiting Bacterial Lipocalin Antibiotic BindingBacteria exposed to stress mediated by sublethal antibiotic concentrations respond by adaptive mechanisms leading to an overall increase of antibiotic resistance. One of these mechanisms involves the release of bacterial proteins called lipocalins, which have the ability to sequester antibiotics in the extracellular space before they reach bacterial cells. We speculated that interfering with lipocalin-mediated antibiotic binding could...
Research Article | Therapeutics and PreventionThe Biofilm Inhibitor Carolacton Enters Gram-Negative Cells: Studies Using a TolC-Deficient Strain of Escherichia coliThe emergence of pathogens resistant against most or all of the antibiotics currently used in human therapy is a global threat, and therefore the search for antimicrobials with novel targets and modes of action is of utmost importance. The myxobacterial secondary metabolite carolacton had previously been shown to inhibit biofilm formation and growth of streptococci. Here, we investigated if carolacton could act against Gram-negative...
Research Article | Clinical Science and EpidemiologyComparison of the Microbiota of Older Adults Living in Nursing Homes and the CommunityThe nose, throat, and skin over the subclavian and femoral veins are the body sites which harbor the bacteria which most commonly cause health care-associated infection. We assessed the effect of nursing home residence on the microbiota of these body sites in older adults. We found that the microbiota composition of the different body sites was similar between nursing home and community participants, but we identified differences in...
Research Article | Molecular Biology and PhysiologySelectable Markers for Use in Genetic Manipulation of Extensively Drug-Resistant (XDR) Acinetobacter baumannii HUMC1Multidrug-resistant (MDR), extensively drug-resistant (XDR), and pan-drug-resistant (PDR) strains of Acinetobacter baumannii have frequently been characterized. The ability of A. baumannii to develop resistance to antibiotics is a key reason this organism has been difficult to study using genetic...
Research Article | Clinical Science and EpidemiologyGlobal Assessment of the Activity of Tigecycline against Multidrug-Resistant Gram-Negative Pathogens between 2004 and 2014 as Part of the Tigecycline Evaluation and Surveillance TrialMultidrug resistance among bacterial pathogens is an ongoing global problem and renders antimicrobial agents ineffective at treating bacterial infections. In the health care setting, infections caused by multidrug-resistant (MDR) Gram-negative bacteria can cause increased mortality, longer hospital stays, and higher treatments costs. The aim of the Tigecycline Evaluation and Surveillance Trial (TEST) is to assess the in vitro...