Bacitracin-resistant Staphylococcus aureus induced in chicken gut and in vitro under bacitracin exposure.

It is common knowledge that prolonged and excessive use of antibiotics can lead to antimicrobial resistance. However, the characteristics and mechanism of resistant-bacteria induced by clinically recommended and prophylactic dose drugs remain largely unclear. This study aimed to observe the trends of drug resistance of the bacitracin-susceptible Staphylococcus aureus strain FS127 under exposure to bacitracin (BAC), which were induced in vitro and in chicken gut.

CRISPR-Cas systems target endogenous genes to impact bacterial physiology and alter mammalian immune responses.

CRISPR-Cas systems are an immune defense mechanism that is widespread in archaea and bacteria against invasive phages or foreign genetic elements. In the last decade, CRISPR-Cas systems have been a leading gene-editing tool for agriculture (plant engineering), biotechnology, and human health (e.g.

Phenotypic and Genotypic Characterization of Multidrug-Resistant Enterobacter hormaechei Carrying Gene Isolated from Chicken Feed in China.

Multidrug resistance (MDR) in Enterobacteriaceae including resistance to quinolones is rising worldwide. The plasmid-mediated quinolone resistance (PMQR) gene is prevalent in Enterobacteriaceae. However, the gene is rarely found in Enterobacter hormaechei ().

Bacterial Multidrug Efflux Pumps at the Frontline of Antimicrobial Resistance: An Overview.

Multidrug efflux pumps function at the frontline to protect bacteria against antimicrobials by decreasing the intracellular concentration of drugs. This protective barrier consists of a series of transporter proteins, which are located in the bacterial cell membrane and periplasm and remove diverse extraneous substrates, including antimicrobials, organic solvents, toxic heavy metals, etc., from bacterial cells.

Enrofloxacin Promotes Plasmid-Mediated Conjugation Transfer of Fluoroquinolone-Resistance Gene .

This study aimed to determine the effect of enrofloxacin (ENR) on the transfer of the plasmid-mediated quinolone resistance (PMQR) gene from opportunistic pathogen (E2) to Enteritidis (SE211) and to analyze the resistance characteristics of SE211- isolates. The plasmid carrying gene of E2 was sequenced by Oxford Nanopore technology. The plasmid carrying gene belonged to incompatibility group IncY.

Antimicrobial resistance and population genomics of multidrug-resistant Escherichia coli in pig farms in mainland China.

The expanding use of antimicrobials in livestock is an important contributor to the worldwide rapid increase in antimicrobial resistance (AMR). However, large-scale studies on AMR in livestock remain scarce. Here, we report findings from surveillance of E.

Virulence Comparison of Subsp. Isolates from Chicken and Whole Genome Analysis of the High Virulent Strain . Enteritidis 211.

Background: is one of the common pathogens in both humans and animals that causes salmonellosis and threatens public health all over the world.

Methods And Results: Here we determined the virulence phenotypes of nine subsp. () isolates in vitro and in vivo, including pathogenicity to chicken, cell infection, biofilm formation and virulence gene expressions.

Longitudinal Surveillance and Risk Assessment of Resistance in to Enrofloxacin from A Large-Scale Chicken Farm in Hebei, China.

The purpose of this study was to investigate the changes of resistance phenotype and plasmid-mediated quinolone resistance genes (PMQRs) in () during enrofloxacin (ENR) administration in different breeding cycles. In 2020, 983 strains of were isolated from different samples in different cycles at the broiler farm with the largest single batch of slaughter capacity in Hebei Province, China. All samples were from chicken, environmental, and human sources.

Preparation of monoclonal antibody and development of an enzyme-linked immunosorbent assay for the detection of ceftiofur in animal-derived foods.

Ceftiofur (CEF) residues in animal-derived foods are of great concern to farmers, regulatory agencies and consumers. In this study, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) method was established to quickly monitor CEF residues in edible animal tissues using an easy sample preparation procedure. A monoclonal antibody, 4D5, against CEF has been produced at first, which had IC values for CEF, ceftriaxone, cefquinome, cefotaxime and desfuroylceftiofur of 0.

Cleavage of E-cadherin by porcine respiratory bacterial pathogens facilitates airway epithelial barrier disruption and bacterial paracellular transmigration.

Airway epithelial cells are the first line of defense against respiratory pathogens. Porcine bacterial pathogens, such as () , and , breach this barrier to lead to local or systematic infections. Here, we demonstrated that respiratory bacterial pathogen infection disrupted the airway epithelial intercellular junction protein, E-cadherin, thus contributing to impaired epithelial cell integrity.

Meningitic Escherichia coli α-hemolysin aggravates blood-brain barrier disruption via targeting TGFβ1-triggered hedgehog signaling.

Bacterial meningitis is a life-threatening infectious disease with severe neurological sequelae and a high mortality rate, in which Escherichia coli is one of the primary Gram-negative etiological bacteria. Meningitic E. coli infection is often accompanied by an elevated blood-brain barrier (BBB) permeability.

miR-155 and miR-146a collectively regulate meningitic Escherichia coli infection-mediated neuroinflammatory responses.

Background: Escherichia coli is the most common Gram-negative bacterium causing meningitis, and E. coli meningitis is associated with high mortality and morbidity throughout the world. Our previous study showed that E.

Sialylated Lipooligosaccharide Contributes to Penetration of Porcine Respiratory Epithelial Barrier.

Pathogens utilize various mechanisms to escape host immunological surveillance, break down different tissue barriers, and cause infection. Sialylation is an important surface modification of bacterial outer membrane components, especially the lipooligosaccharide of Gram-negative bacteria. It is widely involved in multiple microbe-host interactions, such as bacterial virulence regulation, host recognition, and immune evasion.

The Spectrum of Antimicrobial Activity of Cyadox against Pathogens Collected from Pigs, Chicken, and Fish in China.

Cyadox has potential use as an antimicrobial agent in animals. However, its pharmacodynamic properties have not been systematically studied yet. In this study, the in vitro antibacterial activities of cyadox were assayed, and the antibacterial efficacy of cyadox against facultative anaerobes was also determined under anaerobic conditions.

Astrocyte-Derived TGFβ1 Facilitates Blood-Brain Barrier Function via Non-Canonical Hedgehog Signaling in Brain Microvascular Endothelial Cells.

The blood-brain barrier is a specialized structure in mammals, separating the brain from the bloodstream and maintaining the homeostasis of the central nervous system. The barrier is composed of various types of cells, and the communication between these cells is critical to blood-brain barrier (BBB) function. Here, we demonstrate the astrocyte-derived TGFβ1-mediated intercellular communication between astrocytes and brain microvascular endothelial cells (BMECs).

Development of Resistance in ATCC25922 under Exposure of Sub-Inhibitory Concentration of Olaquindox.

Quinoxaline1,4-di--oxides (QdNOs) are a class of important antibacterial drugs of veterinary use, of which the drug resistance mechanism has not yet been clearly explained. This study investigated the molecular mechanism of development of resistance in () under the pressure of sub-inhibitory concentration (sub-MIC) of olaquindox (OLA), a representative QdNOs drug. In vitro challenge of with 1/100× MIC to 1/2× MIC of OLA showed that the bacteria needed a longer time to develop resistance and could only achieve low to moderate levels of resistance as well as form weak biofilms.

Holistic insights into meningitic infection of astrocytes based on whole transcriptome profiling.

To investigate the mRNAs and noncoding RNAs (ncRNAs) expression in astrocytes upon meningitic- infection. The transcription of mRNAs and ncRNAs were fully investigated and profiled by whole transcriptome sequencing and bioinformatic approaches. Whole transcriptome differences between the infected astrocytes and brain microvascular endothelial cells were further compared and characterized.

Antibacterial activity of cyadox against Clostridium perfringens in broilers and a dosage regimen design based on pharmacokinetic-pharmacodynamic modeling.

Necrotic enteritis is an intestinal disease caused by Clostridium perfringens (C. perfringens) that results in high economic losses to the poultry industry. The purpose of this study was to investigate the antibacterial activity of cyadox against C.

CRISPR- of Upregulates Bacterial Biofilm Formation and Virulence to Host Cells by Targeting Quorum-Sensing Systems.

is recognized as one of the most common microbial pathogens worldwide. The bacterium contains the clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) systems, providing adaptive immunity against invading foreign nucleic acids. Previous studies suggested that certain bacteria employ the Cas proteins of CRISPR-Cas systems to target their own genes, which also alters the virulence during invasion of mammals.

Selection and dissemination of antimicrobial resistance in Agri-food production.

Public unrest about the use of antimicrobial agents in farming practice is the leading cause of increasing and the emergences of Multi-drug Resistant Bacteria that have placed pressure on the agri-food industry to act. The usage of antimicrobials in food and agriculture have direct or indirect effects on the development of Antimicrobial resistance (AMR) by bacteria associated with animals and plants which may enter the food chain through consumption of meat, fish, vegetables or some other food sources. In addition to antimicrobials, recent reports have shown that AMR is associated with tolerance to heavy metals existing naturally or used in agri-food production.

Molecular Characterization and Biological Function of a Novel LncRNA CRNG in Swine.

Our previous study has showed that a novel gene is differentially expressed in the liver of cyadox-fed piglets, but its sequence and function are unknown. Here, rapid amplification of cDNA ends (RACE) and bioinformatics analysis showed that the novel gene is 953 bp without protein-coding ability and locates in chromosome 11. Hence, we identified the novel gene as long non-coding RNA (lncRNA) and named it cyadox-related novel gene (CRNG).

Resistance and Virulence Mechanisms of Selected by Enrofloxacin in Chicken.

This study aimed to investigate the genetic characteristics, antibiotic resistance patterns, and novel mechanisms involved in fluoroquinolone (FQ) resistance in commensal isolates. The isolates were recovered from a previous clinical study and subjected to antimicrobial susceptibility testing and molecular typing. Known mechanisms of FQ resistance (target site mutations, plasmid-mediated quinolone resistance [PMQR] genes, relative expression levels of efflux pumps and porins) were detected using DNA sequencing of PCR products and real-time quantitative PCR.