Molecular characterization of the (M)-carrying transposon Tn and plasmids in isolates recovered from swine.

Here, we report the genetic features and evolutionary mechanisms of two (M)-bearing plasmids (pTA2 and pTA7) recovered from swine isolates. The genetic profiles of pTA2 and pTA7 and corresponding transconjugants were accessed by S1 nuclease pulsed-field gel electrophoresis and Southern hybridization, followed by whole genome sequencing and bioinformatics analysis. The biological influences of pTA2 and pTA7 were determined by stability and direct competition assays.

Colistin-niclosamide-loaded nanoemulsions and nanoemulsion gels for effective therapy of colistin-resistant infections.

Colistin (COL) is regarded as a last-resort treatment for infections by multidrug-resistant (MDR) Gram-negative bacteria. The emergence of colistin-resistant Enterobacterales poses a significant global public health concern. Our study discovered that niclosamide (NIC) reverses COL resistance in via a checkerboard assay.

Colistin-niclosamide effervescent dry suspension combats colistin-resistant Salmonella in vitro and in vivo.

The increasing incidence of bacterial infections caused by multidrug-resistant (MDR) Gram-negative bacteria has deepened the need for new effective treatments. It has been reported that niclosamide (NIC) can restore the sensitivity of Gram-negative bacteria to colistin (COL). However, NIC is practically insoluble in water and sparingly soluble in organic solvents, leading to limited therapeutic applications.

Genomic insight into the diversity of isolates from 19 countries.

is a commensal bacterial organism found in the upper respiratory tract of healthy pigs and the etiological agent of Glässer's disease, which causes severe economic losses in the swine industry. This study aimed to better understand the epidemiological characteristics of this opportunistic pathogen. We investigated the prevalence and distribution of sequence types (STs), serovars, antimicrobial resistance genes (ARGs), and potential virulence factors (VFs) in 764 .

Restoring colistin sensitivity in colistin-resistant and : combinatorial use of berberine and EDTA with colistin.

Unlabelled: The appearance and prevalence of multidrug-resistance (MDR) Gram-negative bacteria (GNB) have limited our antibiotic capacity to control bacterial infections. The clinical efficacy of colistin (COL), considered as the "last resort" for treating GNB infections, has been severely hindered by its increased use as well as the emergence and prevalence of mobile colistin resistance (MCR)-mediated acquired drug resistance. Identifying promising compounds to restore antibiotic activity is becoming an effective strategy to alleviate the crisis of increasing MDR.

Horizontal transfer characterization of ColV plasmids in bla-bearing avian Escherichia coli.

Extended-spectrum-β-lactamases (ESBLs)-producing Escherichia coli conferred resistance to most β-lactams, except for carbapenems. To date, the transmission mechanism of bla, as the most common ESBLs subtype, in E. coli has received sustained attention around the worldwide, but the research on the pathogenicity of bla-bearing E.

Upregulation of outer membrane porin gene contributed to enhancement of azithromycin susceptibility in multidrug-resistant .

The outer membrane (OM) in gram-negative bacteria contains proteins that regulate the passive or active uptake of small molecules for growth and cell function, as well as mediate the emergence of antibiotic resistance. This study aims to explore the potential mechanisms for restoring bacteria to azithromycin susceptibility based on transcriptome analysis of bacterial membrane-related genes. Transcriptome sequencing was performed by treating multidrug-resistant T28R with azithromycin or in combination with colistin and confirmed by reverse transcription-quantitative PCR (RT-qPCR).

The antihelminth drug rafoxanide reverses chromosomal-mediated colistin-resistance in .

The emergence and rapid spread of multi-drug-resistant (MDR) bacteria pose a serious threat to global healthcare. Although the synergistic effect of rafoxanide and colistin was reported, little is known regarding the potential mechanism of this synergy, particularly against chromosomal-mediated colistin-resistant . In the present study, we elucidated the synergistic effect of rafoxanide and colistin against chromosomal-mediated colistin-resistant isolates from human (KP-9) and swine (KP-1) infections.

Epidemic characteristics of the SXT/R391 integrated conjugative elements in multidrug-resistant Proteus mirabilis isolated from chicken farm.

This study was designed to depict prevalence and antimicrobial resistance characteristics of Proteus mirabilis (P. mirabilis) strains in 4 chicken farms and to probe the transfer mechanism of resistance genes. A total of 187 P.

Characterization of a Tigecycline-Resistant and -Bearing Klebsiella pneumoniae Strain from a Peacock in a Chinese Zoo.

In Chinese zoos, there are usually specially designed bird parks, similar to petting zoos, that allow children and adults to interact with diverse birds. However, such behaviors present a risk for the transmission of zoonotic pathogens. Recently, we isolated eight strains of Klebsiella pneumoniae and identified two -positive strains from 110 birds, including parrots, peacocks, and ostriches, using anal or nasal swabs in a bird park of a zoo in China.

ICEGpa1804, a novel integrative and conjugative element carrying eight resistance genes, identified in Glaesserella parasuis.

ICEGpa1804 was identified in the genome of a serovar 2, ST279 isolate EHP1804 carrying eight different resistance genes from 200 Glaesserella parasuis strains isolated from swine with lower respiratory tract infection in seven provinces of China. Susceptibility testing for EHP1804 was determined by broth microdilution, and its genetic profile was determined by whole-genome sequencing. The complete ICEGpa1804 was analysed by polymerase chain reaction, conjugation assay and bioinformatics tools.

Synergistic antibacterial activity of baicalin and EDTA in combination with colistin against colistin-resistant Salmonella.

The emergence and rapid spread of multidrug resistant (MDR) Gram-negative bacteria have posed a serious threat to global health and security. Because of the time-consuming, high cost and high risk of developing new antibiotics, a significant method is to use antibiotic adjuvants to revitalize the existing antibiotics. The purpose of the study is to research the traditional Chinese medicine baicalin with the function of inhibiting the efflux pump and EDTA whether their single or combination can increase the activity of colistin against colistin-resistant Salmonella in vitro and in vivo, and to explore its molecular mechanisms.

Decreased cyclic-AMP caused by ATP contributes to fosfomycin heteroresistance in avian Escherichia coli.

Background: Fosfomycin is an important broad-spectrum bactericidal antibiotic to treat multidrug-resistant bacteria infections. It is generally accepted that heteroresistant bacteria are an intermediate stage in the formation of drug resistance, but there are few studies on the formation mechanism underlying fosfomycin heteroresistance (FHR).

Objectives: To reveal the characteristics and formation mechanisms of FHR in Escherichia coli isolates obtained from chickens.

Characterization of IncI1/ST71 and IncF18:A-:B1 multidrug-resistance plasmids from an avian Escherichia coli isolate.

To characterize IncI1 and IncF18:A-:B1 multidrug-resistance plasmids from an avian Escherichia coli isolate, antibiotic susceptibility testing, conjugation assays, transformation assays, S1-PFGE, and WGS analysis were performed. The 119,457-bp plasmid pEC014-1 with a multidrug-resistance region (MRR) containing four different segments interspersed with six IS26 elements, belonged to incompatibility group I1 and sequence type 71. The 154,516-bp plasmid pEC014-2 with two replicons, typed as FII-18 and FIB-1, carried 14 resistance determinants including bla, bla, oqxAB, dfrA17, aac(6')-Ib-cr, sul1, sul2, tet(A), floR, catB3, hph(aph(4)-Ia), aacC4(aac(3)-IV), aadA5, arr-3, and a merEDACPTR loci in MRR, and additionally encoded three virulence loci: iroNEDCB, sitABCD, and iucABCD-iutA.

Genomic insight into the integrative conjugative elements from ICE family.

Integrative conjugative elements (ICEs) are important carriers for disseminating resistance genes. We have previously reported a novel element ICE carrying seven antibiotic resistance genes, which could be self-transmissible relying on the novel T4SS. To identify novel ICE variants from 211 strains and novel T4SS encoded in ICE, and to explore the relationships in these ICEs, four complete sequences of ICEs were identified by WGS analysis and antimicrobial susceptibility testing was determined by broth microdilution.

CpxR negatively regulates IncFII-replicon plasmid pEC011 conjugation by directly binding to multi-promoter regions.

CpxAR is a global regulatory protein and has important roles in plasmid mating. However, except for traJ, the regulatory effect of CpxAR on other tra genes is unclear. The aim of this study was to explore the effects of CpxAR on conjugative transfer of the epidemic plasmid pEC011 (IncFII replicon) in Escherichia coli.

Multidrug Resistance Genes Carried by a Novel Transposon Tn and a Genomic Island Named MMGI-4 in a Pathogenic Morganella morganii Isolate.

Antimicrobial resistance in Morganella morganii is increasing in recent years, which is mainly introduced via extra genetic and mobile elements. The aim of our study is to analyze the multidrug resistance (MDR) and characterize the mobile genetic elements (MGEs) in M. morganii isolates.

Synergistic antibacterial activity of tetrandrine combined with colistin against MCR-mediated colistin-resistant Salmonella.

It has been recognized that colistin resistance is a growing problem that seriously impairs the clinical efficacy of colistin against bacterial infections. One strategy that has been proven to have therapeutic effect is to overcome the widespread emergence of antibiotic-resistant pathogens by combining existing antibiotics with promising non-antibiotic agents. In this work, antibiotic susceptibility testing, checkerboard assays and time-kill curves were used to investigate the antibacterial activity of the individual drugs and the potential synergistic activity of the combination.

Spreading Advantages of Coresident Plasmids -Bearing IncFII and -Bearing IncI2 in Escherichia coli.

Two diverse conjugative plasmids can interact within bacterial cells. However, to the best of our knowledge, the interaction between -bearing IncFII plasmid and -carrying IncI2 plasmid colocated on the same bacterial host has not been reported. This study was initiated to explore the interaction and to analyze the reasons that these two plasmids are often coresident in multidrug-resistant Escherichia coli.

Characterization of a Novel Linezolid Resistance Gene and Bacitracin Resistance Locus-Carrying Multiple Antibiotic Resistant Integrative and Conjugative Element ICE1112S in .

Streptococcus suis strain 1112S was isolated from a diseased pig in a feedlot from Henan, China, in 2019. The isolate harbored a linezolid resistance gene . WGS data revealed that the gene was associated with a single copy ETAf IS, in tandem with (B) and (O), located in a novel 72,587 bp integrative and conjugative element (ICE).