Tn-mediated transfer of from to an outbreak clone of .

Carriage of CTX-M-type extended-spectrum β-lactamase (ESBL) is rare in . During routine surveillance of an endemic ST-621 at a large hospital, isolate MRSN 100690 carrying was cultured from a patient (P2). This was the first detection of this ESBL in the endemic ST-621 lineage.

Detection of cefiderocol and aztreonam/avibactam resistance in epidemic ST-361 carrying and from foreign fighters evacuated from Ukraine.

Genomic surveillance detected clonal sequence type-361 isolates carrying , , , and from a patient in Ukraine and four wounded foreign soldiers evacuated to Germany. Isolates were non-susceptible to carbapenems, aminoglycosides, and cefiderocol and aztreonam/avibactam due to a PBP3 YRIN insertion and the AmpC β-lactamase. Coordinated surveillance efforts across civilian, military, and veteran healthcare systems are essential to prevent further spread as international volunteers return home after medical evacuation from Ukraine.

Deciphering the relative importance of genetic elements in hypervirulent Klebsiella pneumoniae to guide countermeasure development.

Background: Quantitating the contribution of phenotype-responsible elements in hypervirulent Klebsiella pneumoniae is needed.

Methods: Isogenic mutants of four hypervirulent clinical isolates that produced K1 (ST23), K2 (ST86), K20 (ST1544), or K54 (ST29) capsules (mean 2.2 log LD (range 1.

Differentiation of hypervirulent and classical with acquired drug resistance.

Distinguishing hypervirulent (hvKp) from classical (cKp) strains is important for clinical care, surveillance, and research. Some combinations of and are most commonly used, but it is unclear what combination of genotypic or phenotypic markers (e.g.

Differentiation of hypervirulent and classical with acquired drug resistance.

Unlabelled: Distinguishing hypervirulent (hvKp) from classical (cKp) strains is important for clinical care, surveillance, and research. Some combination of and are most commonly used, but it is unclear what combination of genotypic or phenotypic markers (e.g.

Identification of an Outbreak Cluster of Extensively Antibiotic-Resistant GC1 Acinetobacter baumannii Isolates in U.S. Military Treatment Facilities.

An outbreak involving an extensively antibiotic-resistant Acinetobacter baumannii strain in three military treatment facilities was identified. Fifty-nine isolates recovered from 30 patients over a 4-year period were found among a large collection of isolates using core genome multilocus sequence typing (MLST). They differed by only 0 to 18 single nucleotide polymorphisms (SNPs) and carried the same resistance determinants except that the gene was missing in 25 isolates.

A one-year genomic investigation of Escherichia coli epidemiology and nosocomial spread at a large US healthcare network.

Background: Extra-intestinal pathogenic Escherichia coli (ExPEC) are a leading cause of bloodstream and urinary tract infections worldwide. Over the last two decades, increased rates of antibiotic resistance in E. coli have been reported, further complicating treatment.

IS-mediated plasmid reshuffling results in convergence of toxin-antitoxin systems but loss of resistance genes in XDR from a chronic infection.

Carbapenem-resistant pose an urgent threat to human health worldwide. sequence type (ST) 14, initially identified in the Middle East and South-Asia and co-harbouring the carbapenemase genes and is now emerging globally. One such strain was detected in the USA in 2013 from a patient initially treated in India that also carried , a 16S rRNA methyltransferase that confers resistance to all clinically relevant aminoglycosides.

Unsweetened and sucrose-sweetened black and green tea modifies the architecture of in vitro oral biofilms.

Objective: It is unclear whether tea infusions with or without sucrose supplementation alter oral biofilm development, so we evaluated the effect of unsweetened and sucrose-sweetened black and green tea infusions on in vitro saliva-derived biofilms.

Design: Biofilms were developed from human saliva for 20 h in cell-free 25% human saliva within static glass-bottom microplates. During biofilm development, biofilms were treated with either (i) unsweetened black tea, (ii) unsweetened green tea, (iii) 10% sucrose-sweetened black tea, (iv) 10% sucrose-sweetened green tea (v) deionized water (negative control), or (vi) 10% sucrose (positive control).

In vitro model systems for exploring oral biofilms: From single-species populations to complex multi-species communities.

Numerous in vitro biofilm model systems are available to study oral biofilms. Over the past several decades, increased understanding of oral biology and advances in technology have facilitated more accurate simulation of intraoral conditions and have allowed for the increased generalizability of in vitro oral biofilm studies. The integration of contemporary systems with confocal microscopy and 16S rRNA community profiling has enhanced the capabilities of in vitro biofilm model systems to quantify biofilm architecture and analyse microbial community composition.

Introducing BAIT (Biofilm Architecture Inference Tool): a software program to evaluate the architecture of oral multi-species biofilms.

Biofilm model systems are used to study biofilm growth and predict the effects of anti-biofilm interventions within the human oral cavity. Many in vitro biofilm model systems use a confocal laser scanning microscope (CLSM) in conjunction with image analysis tools to study biofilms. The aim of this study was to evaluate an in-house developed image analysis software program that we call BAIT (Biofilm Architecture Inference Tool) to quantify the architecture of oral multi-species biofilms following anti-biofilm interventions using a microfluidic biofilm system.

A Sensitive Thresholding Method for Confocal Laser Scanning Microscope Image Stacks of Microbial Biofilms.

Biofilms are surface-attached microbial communities whose architecture can be captured with confocal microscopy. Manual or automatic thresholding of acquired images is often needed to help distinguish biofilm biomass from background noise. However, manual thresholding is subjective and current automatic thresholding methods can lead to loss of meaningful data.

Coaggregation occurs between microorganisms isolated from different environments.

Coaggregation, the specific recognition and adherence of different microbial species, is thought to enhance biofilm formation. To date, no studies have focused on the ability of microorganisms isolated from a broad range of environments to coaggregate with each other and it is unclear whether coaggregation promotes the transmission of microorganisms between environmental niches. We aimed to evaluate the coaggregation ability of 29 bacteria and one fungus, isolated from a range of different environments, and to characterize the cell-surface polymers that mediate coaggregation between selected pairs.

Association of blaOXA-23 and bap with the persistence of Acinetobacter baumannii within a major healthcare system.

Objectives: Acinetobacter baumannii is an emerging opportunistic nosocomial pathogen. Two factors that may enhance persistence in healthcare settings are antimicrobial resistance and biofilm-forming ability. The aim of this work was to determine whether A.

Use of a high-throughput in vitro microfluidic system to develop oral multi-species biofilms.

There are few high-throughput in vitro systems which facilitate the development of multi-species biofilms that contain numerous species commonly detected within in vivo oral biofilms. Furthermore, a system that uses natural human saliva as the nutrient source, instead of artificial media, is particularly desirable in order to support the expression of cellular and biofilm-specific properties that mimic the in vivo communities. We describe a method for the development of multi-species oral biofilms that are comparable, with respect to species composition, to supragingival dental plaque, under conditions similar to the human oral cavity.