Antibiotic resistance genes in bacteria: Occurrence, spread, and control

Distinct species turnover patterns shaped the richness of antibiotic resistance genes on eight different microplastic polymers

Elucidating the formation mechanism of plastisphere antibiotic resistance genes (ARGs) on different polymers is necessary to understand the ecological risks of plastisphere ARGs. Here, we explored the turnover and assembly mechanism of plastisphere ARGs on 8 different microplastic polymers (4 biodegradable (bMPs) and 4 non-biodegradable microplastics (nMPs)) by metagenomic sequencing. Our study revealed the presence of 479 ARGs with abundance ranging from 41.37 to 58.17 copies/16S rRNA gene in all plastispheres. These ARGs were predominantly multidrug resistance genes. The richness of plastisphere ARGs on different polymers had a significant correlation with the contribution of species turnover to plastisphere ARGs β diversity. Furthermore, polymer type was the most critical factor affecting the composition of plastisphere ARGs. More opportunistic pathogens carrying diverse ARGs on BMPs (PBAT, PBS, and PHA) with higher horizontal gene transfer potential may further magnify the ecological risks and human health threats. For example, the opportunistic pathogens Riemerella anatipestifer, Vibrio campbellii, and Vibrio cholerae are closely related to human production and life, which were the important potential hosts of many plastisphere ARGs and mobile genetic elements on BMPs. Thus, we emphasize the urgency of developing the formation mechanism of plastisphere ARGs and the necessity of controlling BMPs and ARG pollution, especially BMPs, with ever-increasing usage in daily life.

Hydraulic conditions control the abundance of antibiotic resistance genes and their potential host microorganisms in a frequently regulated river-lake system

Antibiotic resistance genes (ARGs) are a growing problem that is widespread in river-lake ecosystems, where they pose a threat to the aquatic environment's health and public safety. These systems serve as critical nodes in water management, as they facilitate the equitable allocation of water resources through long-term and frequent water diversions. However, hydrological disturbances associated with water-regulation practices can influence the dynamics of their potential host microorganisms and associated resistance genes. Consequently, identifying the key ARGs and their resistance mechanisms in heavily regulated waters is vital for safeguarding human health and that of river-lake ecosystems. In this study, we examined the impact of water-regulation factors on ARGs and their hosts within a river-lake continuum using 16S rRNA and metagenomic sequencing. We found that a significant increase in ARG abundance during regulation periods (p < 0.05), especially in the aquatic environment. Key resistance genes were macB, tetA, evgS, novA, and msbA, with increased efflux pinpointed as their principal resistance mechanism. Network analysis identified Flavobacteriales, Acinetobacter, Pseudomonas, Burkholderiaceae, and Erythrobacter as key potential host microorganisms, which showed increased abundance within the water column during regulation periods (p < 0.05). Flow velocity and water depth both drove the host microorganisms and critical ARGs. Our findings underscore the importance of monitoring and mitigating the antibiotic resistance risk during water transfers in river-lake systems, thereby supporting informed management and conservation strategies.

Retention of methicillin susceptibility in Staphylococcus aureus using natural adjuvant as an allosteric modifier of penicillin-binding protein 2a

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) poses a significant global public health challenge due to its resistance to conventional antibiotics, primarily mediated by the mutated penicillin-binding protein, PBP2a. This study aims to investigate the potential of phytochemicals derived from medicinal plants in the Indian subcontinent to serve as adjuvants, enhancing the efficacy of methicillin against MRSA through allosteric modification of PBP2a using molecular docking and molecular dynamics (MD) simulation. After comprehensive Absorption, Distribution, Metabolism, and Excretion (ADME) profiling, along with AMES and hepatotoxicity tests, 9 compounds were shortlisted as suitable adjuvant candidates. Among them, nimbolide, quercetin, emodin, daidzein, eriodictyol, luteolin, and apigenin exhibited strong binding affinity to the allosteric site of PBP2a, with docking scores ranging from -8.7 to -7.3 kcal/mol. These phytochemicals facilitated enhanced methicillin binding, as evidenced by improved docking scores ranging from -6.1 to -6.8 kcal/mol, compared to -5.6 kcal/mol for methicillin alone. Molecular dynamics simulations confirmed the stability and favorable conformations of phytochemical-PBP2a complexes. Quercetin and daidzein were identified as the most promising adjuvant candidates, forming stable and energetically favorable complexes with PBP2a. Experimental validation showed that quercetin, at 30 mg/mL, effectively retained methicillin's antibacterial efficacy against MRSA. This study underscores the potential of natural compounds in overcoming antibiotic resistance and suggests that phytochemical-antibiotic synergism could be a viable strategy to combat multidrug-resistant bacterial infections.

Assessment of the Safety and Exopolysaccharide Synthesis Capabilities of Bacillus amyloliquefaciens D189 Based on Complete Genome and Phenotype Analysis

Exopolysaccharides (EPS) are natural macromolecular carbohydrates with good functional activity and physiological activities, which can be utilized as an emulsifier, viscosity enhancer, stabilizer, gelling agent, and water retention agent in a wide range of food products. In this study, the whole genome of Bacillus amyloliquefaciens D189, an EPS-producing bacteria, was sequenced. The result showed that D189 contains a single, circular chromosome of 3,963,356 bp with an average GC content of 45.74% and 3996 coding genes. The gene annotation results showed that D189 is a potentially safe strain and confirmed to be safe associated with hemolytic assay, and antibiotic resistance test. Meanwhile, D189 genome possessed 240 genes related to carbohydrate metabolism. More importantly, D189 could transport 9 sugars and contained a complete biosynthetic pathway for 8 nucleotide sugars. Based on the validation experiments, strain D189 could metabolize 8 sugars (glucose, sucrose, trehalose, fructose, cellobiose, maltose, mannitol, and N-acetyl-D-glucosamine) to produce EPS, with the highest yield of 1.212 g/L when sucrose was the carbon source. Therefore, the whole genome sequencing preliminarily elucidated the physiological mechanism of EPS, providing several pathways for engineering D189 to further enhance the yield of EPS.

Electrochemical Sensors for Antibiotic Detection: A Focused Review with a Brief Overview of Commercial Technologies

Antimicrobial resistance (AMR) poses a significant threat to global health, powered by pathogens that become increasingly proficient at withstanding antibiotic treatments. This review introduces the factors contributing to antimicrobial resistance (AMR), highlighting the presence of antibiotics in different environmental and biological matrices as a significant contributor to the resistance. It emphasizes the urgent need for robust and effective detection methods to identify these substances and mitigate their impact on AMR. Traditional techniques, such as liquid chromatography-mass spectrometry (LC-MS) and immunoassays, are discussed alongside their limitations. The review underscores the emerging role of biosensors as promising alternatives for antibiotic detection, with a particular focus on electrochemical biosensors. Therefore, the manuscript extensively explores the principles and various types of electrochemical biosensors, elucidating their advantages, including high sensitivity, rapid response, and potential for point-of-care applications. Moreover, the manuscript investigates recent advances in materials used to fabricate electrochemical platforms for antibiotic detection, such as aptamers and molecularly imprinted polymers, highlighting their role in enhancing sensor performance and selectivity. This review culminates with an evaluation and summary of commercially available and spin-off sensors for antibiotic detection, emphasizing their versatility and portability. By explaining the landscape, role, and future outlook of electrochemical biosensors in antibiotic detection, this review provides insights into the ongoing efforts to combat the escalating threat of AMR effectively.

Multi-locus sequence typing and genetic diversity of antibiotic-resistant genes and virulence-associated genes in Burkholderia pseudomallei: Insights from whole genome sequencing of animal and environmental isolates in Thailand

Burkholderia pseudomallei is a Gram-negative bacillus and the etiological agent of melioidosis in humans and animals. The disease is highly endemic in northern Australia and Southeast Asia. Comprehensive genomic data are essential for understanding the bacteria's dissemination and genetic relationships among strains from different geographical regions. In this study, we conducted antimicrobial susceptibility testing and whole-genome sequencing of 54 B. pseudomallei isolates obtained from environmental and animal sources in southern Thailand between 2011 and 2018. Their genomics were determined of antibiotic-resistant genes (ARGs), virulence-associated genes, mobile genetic elements (MGEs), sequence types (STs), and single nucleotide polymorphisms (SNPs) to evaluate their epidemiological relatedness. Remarkably, all 54 isolates displayed sensitivity to antimicrobial agents typically used for melioidosis treatment. We identified nine distinct sequence types: ST392, ST51, ST409, ST508, ST376, ST1721, ST389, ST395, and ST289. Oxacillinase genes and the resistance nodulation family of efflux pumps (RND) were identified as contributors to antimicrobial resistance. Phylogenetic analysis demonstrated close genetic relations with other strains isolated from Southeast Asia. Furthermore, 172 virulence-associated genes were identified among the isolates, suggesting variations in clinical presentations. These findings underscore the importance of ongoing molecular genetic surveillance of B. pseudomallei for effective healthcare management and reducing melioidosis mortality.

Current Strategy for Targeting Metallo-β-Lactamase with Metal-Ion-Binding Inhibitors

Currently, antimicrobial resistance (AMR) is a serious health problem in the world, mainly because of the rapid spread of multidrug-resistant (MDR) bacteria. These include bacteria that produce β-lactamases, which confer resistance to β-lactams, the antibiotics with the most prescriptions in the world. Carbapenems are particularly noteworthy because they are considered the ultimate therapeutic option for MDR bacteria. However, this group of antibiotics can also be hydrolyzed by β-lactamases, including metallo-β-lactamases (MBLs), which have one or two zinc ions (Zn2+) on the active site and are resistant to common inhibitors of serine β-lactamases, such as clavulanic acid, sulbactam, tazobactam, and avibactam. Therefore, the design of inhibitors against MBLs has been directed toward various compounds, with groups such as nitrogen, thiols, and metal-binding carboxylates, or compounds such as bicyclic boronates that mimic hydrolysis intermediates. Other compounds, such as dipicolinic acid and aspergillomarasmin A, have also been shown to inhibit MBLs by chelating Zn2+. In fact, recent inhibitors are based on Zn2+ chelation, which is an important factor in the mechanism of action of most MBL inhibitors. Therefore, in this review, we analyzed the current strategies for the design and mechanism of action of metal-ion-binding inhibitors that combat MDR bacteria.

Land use conversion to uplands significantly increased the risk of antibiotic resistance genes in estuary area

Land use conversion in estuary wetlands may affect the transmission of antibiotic resistance genes (ARGs), while the risk rank of the ARGs and the change of clinically relevant ARGs under various land-use types are not well understood. This study used metagenomics to reveal the diversity and abundance of ARGs across five distinct land uses: reed wetland, tidal flat, grassland, agricultural land and fallow land, as well as their distribution and potential health risks. Results showed that high numbers of ARG subtypes and classes were detected irrespective of land-use types, notably higher in agricultural land (144 ARG subtypes). The most shared ARG subtypes were multidrug resistance genes across all the land uses (29 subtypes, 4.7 × 10-2-1.5 × 10-1 copies per 16S rRNA gene copy). Proteobacteria and Actinobacteria were primary ARG hosts, with 18 and 15 ARGs were found in both of them, respectively. The ARG subtype mdtB was the most dominant clinical ARG detected with 90 % amino acid identity. The change of ARGs exhibited a consistent trend across land uses in terms of health risk ranks, with the highest observed in fallow land and the lowest in reed wetland. This study reveals the distribution pattern of ARGs across various land-use types, and enhances our understanding of the potential health risks associated with ARGs in the context of coastal wetland conversion in estuary areas.

Coexistence of multidrug resistance and ESBL encoding genes - blaTEM, blaSHV, and blaCTX-M; its amplification and dispersion in the environment via municipal wastewater treatment plant

Municipal wastewater treatment plants (MWWTPs) are a global source of antibiotic resistance genes (ARGs), collecting wastewater from a variety of sources, including hospital wastewater, domestic wastewater, runoff from agricultural and livestock farms, etc. These sources are contaminated with organic and inorganic pollutants, ARGs and antibiotic-resistant bacteria (ARB). Such pollutants aided eutrophication and encouraged bacterial growth. During bacterial growth horizontal gene transfer (HGT) and vertical gene transfer (VGT) of ARGs and extended-spectrum β-lactamase (ESBL) encoding genes may facilitate, resulting in the spread of antibiotic resistance exponentially. The current study investigated the prevalence of multidrug resistance (MDR) and ESBL encoding genes in various treatment units of MWWTP and their spread in the environment. A total of three sampling sites (BUT, BRO, and BFB) were chosen, and 33 morphologically distinct bacterial colonies were isolated. 14 of the 33 isolates tested positive for antibiotic resistance and were further tested for the coexistence of MDR and ESBL production. The selected 14 isolates showed the highest resistance to trimethoprim (85.71%), followed by ciprofloxacin, azithromycin, and ampicillin (71.42%), tetracycline (57.14%), and vancomycin, gentamicin, and colistin sulphate (50%). A total of 9 isolates (64.28%) were phenotypically positive for ESBL production (BUT2, BUT3, BUT5, BRO1, BRO2, BRO3, BRO4, BRO5 and BFB1). The molecular detection of ESBL encoding genes, i.e. blaTEM, blaSHV, and blaCTX-M was carried out. The most prevalent gene was blaTEM (69.23%), followed by blaSHV (46.15%), and blaCTX-M (23.07%). In this study, 9 isolates (64.28%) out of 14 showed the coexistence of MDR and ESBL encoding genes, namely BUT3, BUT4, BUT5, BUT6, BUT7, BRO1, BRO2, BRO4, and BFB1. The coexistence of ESBL encoding genes and resistance to other antibiotic classes exacerbates human health and the environment.

Hospital and municipal wastewater as a source of carbapenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa in the environment: a review

The increase in the prevalence of carbapenem-resistant Gram-negative bacteria, in particular Acinetobacter baumannii (CRAB) and Pseudomonas aeruginosa (CRPA), poses a serious threat for public health worldwide. This article reviews the alarming data on the prevalence of infections caused by CRAB and CRPA pathogens and their presence in hospital and municipal wastewater, and it highlights the environmental impact of antibiotic resistance. The article describes the key role of antibiotic resistance genes (ARGs) in the acquisition of carbapenem resistance and sheds light on bacterial resistance mechanisms. The main emphasis was placed on the transfer of ARGs not only in the clinical setting, but also in the environment, including water, soil, and food. The aim of this review was to expand our understanding of the global health risks associated with CRAB and CRPA in hospital and municipal wastewater and to analyze the spread of these micropollutants in the environment. A review of the literature published in the last decade will direct research on carbapenem-resistant pathogens, support the implementation of effective preventive measures and interventions, and contribute to the development of improved strategies for managing this problem.

Metagenomic insights into effects of carbon/nitrogen ratio on microbial community and antibiotic resistance in moving bed biofilm reactor

This study investigated the effects of carbon/nitrogen (C/N) ratio on microbial community in moving bed biofilm reactor (MBBR) using metagenomic analysis, and the dynamic changes of relevant antibiotic resistance genes (ARGs) were also analyzed. The results showed that under low C/N ratio, MBBR exhibited average removal rates of 98.41 % for ammonia nitrogen and 75.79 % for total nitrogen. Metagenomic analysis showed low C/N ratio altered the structure of biofilm and water microbiota, resulting in the detachment of bacteria such as Actinobacteria from biofilm into water. Furthermore, sulfamethazine (SMZ)-resistant bacteria and related ARGs were released into water under low C/N ratio, which lead to the increase of SMZ resistance rate to 90%. Moreover, most dominant genera are potential hosts for both nitrogen cycle related genes and ARGs. Specifically, Nitrosomonas that carried gene sul2 might be released from biofilm into water. These findings implied the risks of antibiotic resistance dissemination in MBBR under low C/N ratio.

Distribution Patterns and Antibiotic Resistance Profiles of Bacterial Pathogens Among Patients with Wound Infections in the Jiaxing Region from 2021 to 2023

Purpose

To systematically assess the distribution and antimicrobial susceptibility of pathogens in wound infections, and analyze risk factors associated with multidrug resistance (MDR).

Patients and Methods

Retrospectively analyzing Jiaxing-region medical records between January 2021 and December 2023, we identified a cohort of 461 wound infection patients. Cultures were grown on various agars, with bacteria identified via Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry. The antimicrobial susceptibility of the organisms were conducted by VITEK 2 system, Kirby-Bauer disk diffusion method and Epsilometer test. Statistical Package for the Social Sciences (SPSS) version 22 was used for statistical analysis. Multivariable logistic regression models were developed to pinpoint risk factors for multidrug-resistant organism (MDRO) infections and predict occurrences.

Results

From 461 patients, 549 bacterial pathogens were isolated, predominantly consisting of Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, Enterobacter cloacae, and Enterococcus faecalis. Vancomycin, linezolid, and tigecycline maintained their efficacy against Staphylococcus aureus and Enterococcus species, while Pseudomonas aeruginosa demonstrated sensitivity to aminoglycosides. Conversely, Escherichia coli exhibited high amoxicillin resistance (85.4%). More than half of the isolates were resistant to levofloxacin, ceftriaxone, cotrimoxazole, and gentamicin, with Acinetobacter baumannii strains showing considerable resistance (65.8-68.4%) to advanced cephalosporins and carbapenems. Within this group, 58 MDROs were detected, primarily originating from Burn Plastic Surgery, Emergency, and Intensive Care Unit (ICU) departments. Multivariate logistic regression identified hyperglycemia, hypoalbuminemia, surgery, extended hospitalization, and exposure to multiple antibiotic classes as independent risk factors for MDRO wound infections. Based on these findings, a predictive model for MDRO occurrence in wounds was constructed, which had a sensitivity of 0.627, specificity of 0.933, and an Area Under the Curve (AUC) of 0.838.

Conclusion

Staphylococcus aureus and Pseudomonas aeruginosa dominated in wound infections with differential antibiotic resistance. Independent risk factors included hyperglycemia, hypoalbuminemia, surgery, extended hospitalization, and polyantibiotic use. We urge prioritizing culture, susceptibility tests, and personalized antibiotic strategies to address MDRO risks and improve wound infection management specificity and efficacy.

Advantages and drawbacks of life cycle assessment application to the pharmaceuticals: a short critical literature review

Pharmaceuticals are among the most challenging products to assess by life cycle assessment (LCA). The main drawback highlighted by LCA practitioners is the lack of inventory data, both regarding the synthesis of active pharmaceutical ingredient (API) precursors (upstream) and the details concerning the downstream phases (use and end of life). A short critical review of pharma-LCAs found in the literature is here proposed, with discussion of several tools and models used to predict the environmental impacts derived from the life cycle of pharmaceuticals, emphasizing current strengths and weaknesses, and exploring the possibilities for improvements. The case of antibiotics is selected as a representative class of pharmaceuticals, due to their massive use worldwide and the growing related issue of antimicrobial resistance enrichment, which is generally not included in most of LCAs. Also, we comment on drafting product category rules (PCRs) in the relevant field to develop standard methodologies and enhance the comparability of the studies, ultimately advocating collaboration with companies and improving inventory data quality and availability for the whole value chain of products.

Customizable and stable multilocus chromosomal integration: a novel glucose-dependent selection system in Aureobasidium spp

BACKGROUND

Non-conventional yeasts hold significant potential as biorefinery cell factories for microbial bioproduction. Currently, gene editing systems used for these yeasts rely on antibiotic and auxotrophic selection mechanisms. However, the drawbacks of antibiotics, including high costs, environmental concerns, and the dissemination of resistance genes, make them unsuitable for large-scale industrial fermentation. For auxotrophic selection system, the engineered strains harboring auxotrophic marker genes are typically supplemented with complex nutrient-rich components instead of precisely defined synthetic media in large-scale industrial fermentations, thus lack selection pressure to ensure the stability of heterologous metabolic pathways. Therefore, it is a critical to explore alternative selection systems that can be adapted for large-scale industrial fermentation.

RESULTS

Here, a novel glucose-dependent selection system was developed in a high pullulan-producing non-conventional strain A. melanogenum P16. The system comprised a glucose-deficient chassis cell Δpfk obtained through the knockout of the phosphofructokinase gene (PFK) and a series of chromosomal integration plasmids carrying a selection marker PFK controlled by different strength promoters. Utilizing the green fluorescent protein gene (GFP) as a reporter gene, this system achieved a 100% positive rate of transformation, and the chromosomal integration numbers of GFP showed an inverse relationship with promoter strength, with a customizable copy number ranging from 2 to 54. More importantly, the chromosomal integration numbers of target genes remained stable during successive inoculation and fermentation process, facilitated simply by using glucose as a cost-effective and environmental-friendly selectable molecule to maintain a constant and rigorous screening pressure. Moreover, this glucose-dependent selection system exhibited no significant effect on cell growth and product synthesis, and the glucose-deficient related selectable marker PFK has universal application potential in non-conventional yeasts.

CONCLUSION

Here, we have developed a novel glucose-dependent selection system to achieve customizable and stable multilocus chromosomal integration of target genes. Therefore, this study presents a promising new tool for genetic manipulation and strain enhancement in non-conventional yeasts, particularly tailored for industrial fermentation applications.

Tackling Carbapenem Resistance and the Imperative for One Health Strategies-Insights from the Portuguese Perspective

Carbapenemases, a class of enzymes specialized in the hydrolysis of carbapenems, represent a significant threat to global public health. These enzymes are classified into different Ambler's classes based on their active sites, categorized into classes A, D, and B. Among the most prevalent types are IMI/NMC-A, KPC, VIM, IMP, and OXA-48, commonly associated with pathogenic species such as Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The emergence and dissemination of carbapenemase-producing bacteria have raised substantial concerns due to their ability to infect humans and animals (both companion and food-producing) and their presence in environmental reservoirs. Adopting a holistic One Health approach, concerted efforts have been directed toward devising comprehensive strategies to mitigate the impact of antimicrobial resistance dissemination. This entails collaborative interventions, highlighting proactive measures by global organizations like the World Health Organization, the Center for Disease Control and Prevention, and the Food and Agriculture Organization. By synthesizing the evolving landscape of carbapenemase epidemiology in Portugal and tracing the trajectory from initial isolated cases to contemporary reports, this review highlights key factors driving antibiotic resistance, such as antimicrobial use and healthcare practices, and underscores the imperative for sustained vigilance, interdisciplinary collaboration, and innovative interventions to curb the escalating threat posed by antibiotic-resistant pathogens. Finally, it discusses potential alternatives and innovations aimed at tackling carbapenemase-mediated antibiotic resistance, including new therapies, enhanced surveillance, and public awareness campaigns.

Species prevalence, virulence genes, and antibiotic resistance of enterococci from food-producing animals at a slaughterhouse in Turkey

Healthy cattle, sheep, and goats can be reservoirs for gastrointestinal pathogenic fecal enterococci, some of which could be multidrug-resistant to antimicrobials. The objective of this study was to determine the prevalence and diversity of Enterococcus species in healthy sheep, goat, and cattle carcasses, as well as to analyze the antimicrobial resistance phenotype/genotype and the virulence gene content. During 2019-2020, carcass surface samples were collected from 150 ruminants in a slaughterhouse. A total of 90 enterococci, comprising five species, were obtained. The overall prevalence of enterococci was found to be 60%, out of which 37.7% were identified as Enterococcus (E.) hirae, 33.3% as E. casseliflavus, 15.5% as E. faecium, 12.2% as E. faecalis, and 1.1% as E. gallinarum. Virulence-associated genes of efaA (12.2%) were commonly observed in the Enterococcus isolates, followed by gelE (3.3%), asaI (3.3%), and ace (2.2%). High resistance to quinupristin-dalfopristin (28.8%), tetracycline (21.1%), ampicillin (20%), and rifampin (15.5%) was found in two, four, four, and five of the Enterococcus species group, respectively. The resistance of Enterococcus isolates to 11 antibiotic groups was determined and multidrug resistant (MDR) strains were found in 18.8% of Enterococcus isolates. Characteristic resistance genes were identified by PCR with an incidence of 6.6%, 2.2%, 1.1%, 1.1%, 1.1%, and 1.1% for the tetM, ermB, ermA, aac(6')Ie-aph(2")-la, VanC1, and VanC2 genes in Enterococcus isolates, respectively. Efflux pump genes causing multidrug resistance were detected in Enterococcus isolates (34.4%). The results showed that there were enterococci in the slaughterhouse with a number of genes linked to virulence that could be harmful to human health.

The regulatory mechanism of garlic skin improving the growth performance of fattening sheep through metabolism and immunity

Objective

Garlic skin (GAS) has been proven to improve the growth performance of fattening sheep. However, the mechanism by which GAS affects fattening sheep is not yet clear. The aim of this study is to investigate the effects of adding GAS to feed on the growth performance, rumen and fecal microbiota, serum and urine metabolism, and transcriptomics of rumen epithelial cells in fattening sheep.

Methods

GAS with 80 g/kg dry matter (DM) was added to the diet of fattening sheep to study the effects of GAS on gut microbiota, serum and urine metabolism, and transcriptome of rumen epithelial tissue in fattening sheep. Twelve Hu sheep (body weights; BW, 23.0 ± 2.3 kg and ages 120 ± 3.5 d) were randomly divided into two groups. The CON group was the basal diet, while the GAS group was supplemented with GAS in the basal diet. The trial period was 10 weeks, with the first 2 weeks being the pre-trial period.

Results

The daily average weight gain of fattening sheep in the GAS group was significantly higher than that in the CON group (p < 0.05), and the serum GSH-Px of the GAS group fattening sheep was significantly increased, while MDA was significantly reduced (p < 0.05). Based on the genus classification level, the addition of garlic peel in the diet changed the intestinal microbial composition, and the relative abundance was significantly upregulated by Metanobrevibater (p < 0.05), while significantly downregulated by Akkermansia, Parasutterella, and Guggenheimella (p < 0.05). Metabolomics analysis found that there were 166 significantly different metabolites in serum and 68 significantly different metabolites in urine between the GAS and CON groups (p < 0.05). GAS had an impact on amino acid metabolism, pyrimidine metabolism, methane metabolism, riboflavin metabolism, and unsaturated fatty acid synthesis pathways (p < 0.05). Transcriptome sequencing showed that differentially expressed genes were mainly enriched in immune regulatory function, improving the health of fattening sheep.

Conclusion

Adding GAS can improve the energy metabolism and immune function of fattening sheep by altering gut microbiota, metabolome, and transcriptome, thereby improving the growth performance of fattening sheep.

Implications of Artificial Intelligence in Addressing Antimicrobial Resistance: Innovations, Global Challenges, and Healthcare's Future

Antibiotic resistance poses a significant threat to global public health due to complex interactions between bacterial genetic factors and external influences such as antibiotic misuse. Artificial intelligence (AI) offers innovative strategies to address this crisis. For example, AI can analyze genomic data to detect resistance markers early on, enabling early interventions. In addition, AI-powered decision support systems can optimize antibiotic use by recommending the most effective treatments based on patient data and local resistance patterns. AI can accelerate drug discovery by predicting the efficacy of new compounds and identifying potential antibacterial agents. Although progress has been made, challenges persist, including data quality, model interpretability, and real-world implementation. A multidisciplinary approach that integrates AI with other emerging technologies, such as synthetic biology and nanomedicine, could pave the way for effective prevention and mitigation of antimicrobial resistance, preserving the efficacy of antibiotics for future generations.

Impact of low-dose ozone nanobubble treatments on antimicrobial resistance genes in pond water

Antimicrobial resistance (AMR) poses a significant global health threat as the silent pandemic. Because of the use of antimicrobials in aquaculture systems, fish farms may be potential reservoirs for the dissemination of antimicrobial resistance genes (ARGs). Treatments with disinfectants have been promoted to reduce the use of antibiotics; however, the effect of these types of treatments on AMR or ARGs is not well known. This study aimed to evaluate the effects of low dose ozone treatments (0.15 mg/L) on ARG dynamics in pond water using metagenomic shotgun sequencing analysis. The results suggested that ozone disinfection can increase the relative abundance of acquired ARGs and intrinsic efflux mediated ARGs found in the resistance nodulation cell division (RND) family. Notably, a co-occurrence of efflux and non-efflux ARGs within the same bacterial genera was also observed, with most of these genera dominating the bacterial population following ozone treatments. These findings suggest that ozone treatments may selectively favor the survival of bacterial genera harboring efflux ARGs, which may also have non-efflux ARGs. This study underscores the importance of considering the potential impacts of disinfection practices on AMR gene dissemination particularly in aquaculture settings where disinfectants are frequently used at low levels. Future endeavors should prioritize the evaluation of these strategies, as they may be associated with an increased risk of AMR in aquatic environments.

Staphylococcus aureus epidemiology, pathophysiology, clinical manifestations and application of nano-therapeutics as a promising approach to combat methicillin resistant Staphylococcus aureus

Staphylococcus aureus is a Gram-positive bacterium and one of the most prevalent infectious disease-related causes of morbidity and mortality in adults. This pathogen can trigger a broad spectrum of diseases, from sepsis and pneumonia to severe skin infections that can be fatal. In this review, we will provide an overview of S. aureus and discuss the extensive literature on epidemiology, transmission, genetic diversity, evolution and antibiotic resistance strains, particularly methicillin resistant S. aureus (MRSA). While many different virulence factors that S. aureus produces have been investigated as therapeutic targets, this review examines recent nanotechnology approaches, which employ materials with atomic or molecular dimensions and are being used to diagnose, treat, or eliminate the activity of S. aureus. Finally, having a deeper understanding and clearer grasp of the roles and contributions of S. aureus determinants, antibiotic resistance, and nanotechnology will aid us in developing anti-virulence strategies to combat the growing scarcity of effective antibiotics against S. aureus.

Multi-Omics Analysis Reveals the Regulatory Mechanism of Probiotics on the Growth Performance of Fattening Sheep

Probiotics have been proven to improve the growth performance of livestock and poultry. The aim of this experiment was to investigate the effects of probiotic supplementation on the growth performance; rumen and intestinal microbiota; rumen fluid, serum, and urine metabolism; and rumen epithelial cell transcriptomics of fattening meat sheep. Twelve Hu sheep were selected and randomly divided into two groups. They were fed a basal diet (CON) or a basal diet supplemented with 1.5 × 108 CFU/g probiotics (PRB). The results show that the average daily weight gain, and volatile fatty acid and serum antioxidant capacity concentrations of the PRB group were significantly higher than those of the CON group (p < 0.05). Compared to the CON group, the thickness of the rumen muscle layer in the PRB group was significantly decreased (p < 0.01); the thickness of the duodenal muscle layer in the fattening sheep was significantly reduced; and the length of the duodenal villi, the thickness of the cecal and rectal mucosal muscle layers, and the thickness of the cecal, colon, and rectal mucosal layers (p < 0.05) were significantly increased. At the genus level, the addition of probiotics altered the composition of the rumen and intestinal microbiota, significantly upregulating the relative abundance of Subdivision5_genera_incertae_sedis and Acinetobacter in the rumen microbiota, and significantly downregulating the relative abundance of Butyrivibrio, Saccharofermentans, and Fibrobacter. The relative abundance of faecalicoccus was significantly upregulated in the intestinal microbiota, while the relative abundance of Coprococcus, Porphyromonas, and Anaerobacterium were significantly downregulated (p < 0.05). There were significant differences in the rumen, serum, and urine metabolites between the PRB group and the CON group, with 188, 138, and 104 metabolites (p < 0.05), mainly affecting pathways such as vitamin B2, vitamin B3, vitamin B6, and a series of amino acid metabolisms. The differential genes in the transcriptome sequencing were mainly enriched in protein modification regulation (especially histone modification), immune function regulation, and energy metabolism. Therefore, adding probiotics improved the growth performance of fattening sheep by altering the rumen and intestinal microbiota; the rumen, serum, and urine metabolome; and the transcriptome.

Taxonomic Diversity and Functional Traits of Soil Bacterial Communities under Radioactive Contamination: A Review

Studies investigating the taxonomic diversity and structure of soil bacteria in areas with enhanced radioactive backgrounds have been ongoing for three decades. An analysis of data published from 1996 to 2024 reveals changes in the taxonomic structure of radioactively contaminated soils compared to the reference, showing that these changes are not exclusively dependent on contamination rates or pollutant compositions. High levels of radioactive exposure from external irradiation and a high radionuclide content lead to a decrease in the alpha diversity of soil bacterial communities, both in laboratory settings and environmental conditions. The effects of low or moderate exposure are not consistently pronounced or unidirectional. Functional differences among taxonomic groups that dominate in contaminated soil indicate a variety of adaptation strategies. Bacteria identified as multiple-stress tolerant; exhibiting tolerance to metals and antibiotics; producing antioxidant enzymes, low-molecular antioxidants, and radioprotectors; participating in redox reactions; and possessing thermophilic characteristics play a significant role. Changes in the taxonomic and functional structure, resulting from increased soil radionuclide content, are influenced by the combined effects of ionizing radiation, the chemical toxicity of radionuclides and co-contaminants, as well as the physical and chemical properties of the soil and the initial bacterial community composition. Currently, the quantification of the differential contributions of these factors based on the existing published studies presents a challenge.

Response characteristics and functional predictions of soil microorganisms to heavy metals, antibiotics, and their resistance genes originating from different animal farms amended with Herbaspirillum huttiense

Current understanding is limited regarding technologies that use biochar and microorganisms to simultaneously treat soils contaminated with both veterinary antibiotics (VAs) and heavy metals (HMs) from different animal farms. The contributions of the keystone taxa and their similarities from different animal farms under VA and HM stresses before and after soil remediation should be further investigated as well. An innovative treatment of Herbaspirillum huttiense (HHS1) inoculated waste fungus chaff-based (WFCB) biochar was designed for immobilization of copper (Cu) and zinc (Zn), and the removal of oxytetracycline (OTC), enrofloxacin (ENR), and a subsequent reduction in their resistance genes in soils from pig, cow, and chicken farms. Roles of indigenous microorganisms which can treat soils contaminated with VAs and HMs were summarized. Results showed that available Cu and Zn were reduced by 19.5% and 28.1%, respectively, while 49.8% of OTC and 85.1% of ENR were removed by WFCB-HHS1. The decrease in ENR improved overall microbial community diversity, and the increases in genera HHS1, Pedobacter, Flavobacterium and Aequorivita, along with the decreases of genera Bacillus, Methylobacter, and Fermentimonas were indirectly favorable to treat HMs and VAs in soils from different animal farms. Bacterial communities in different animal farm soils were predominantly influenced by stochastic processes. The regulations of functional genes associated with metabolism and environmental information processing, which contribute to HM and VA defense, were altered when using WFCB-HHS1. Furthermore, the spread of their antibiotic resistance genes was restricted.

Causal-ARG: a causality-guided framework for annotating properties of antibiotic resistance genes

MOTIVATION

The crisis of antibiotic resistance, which causes antibiotics used to treat bacterial infections to become less effective, has emerged as one of the foremost challenges to public health. Identifying the properties of antibiotic resistance genes (ARGs) is an essential way to mitigate this issue. Although numerous methods have been proposed for this task, most of these approaches concentrate solely on predicting antibiotic class, disregarding other important properties of ARGs. In addition, existing methods for simultaneously predicting multiple properties of ARGs fail to account for the causal relationships among these properties, limiting the predictive performance.

RESULTS

In this study, we propose a causality-guided framework for annotating properties of ARGs, in which causal inference is utilized for representation learning. More specifically, the hidden biological patterns determining the properties of ARGs are described by a Gaussian Mixture Model, and procedure of causal representation learning is used to derive the hidden features. In addition, a causal graph among different properties is constructed to capture the causal relationships among properties of ARGs, which is integrated into the task of annotating properties of ARGs. The experimental results on a real-world dataset demonstrate the effectiveness of the proposed framework on the task of annotating properties of ARGs.

AVAILABILITY AND IMPLEMENTATION

The data and source codes are available in GitHub at https://github.com/David-WZhao/CausalARG.

Pathogenic potential of meat-borne coagulase negative staphylococci strains from slaughterhouse to fork

This study aimed to determine the prevalence of coagulase-negative staphylococci (CoNS) in meat processing lines for their pathogenic potential associated with biofilm formation, staphylococcal toxin genes, and antibiotic resistance in obtained isolates. Out of 270 samples, 56 isolates were identified as staphylococcal with their species level, and their antimicrobial resistance profiles were also determined with the BD Phoenix™ system. Among these, CoNS were found in 32 isolates, including S. epidermidis (22%), S. warneri (22%), S. cohnii (9%), S. schleiferi (9%), S. capitis (6%), S. haemolyticus (6%), S. lugdunensis (6%), S. chromogenes (6%), S. kloosii (3%), S. sciuri (3%), S. lentus (3%), and S. caprae (3%). Biofilm formation was observed in 78.1% of CoNS isolates, with 56% being strong biofilm producers; and the frequency of the icaA, fnbA, and fnbB genes were 43.7% and 34.3%, and 9.3% in isolates, respectively. Twenty-five (78.1%) of these strains were resistant to at least one antimicrobial agent, 20 (80%) of which exhibited multidrug resistance (MDR). Regarding genotypic analyses, 15.6%, 22.2%, 87.5%, and 9% of isolates, were positive for blaZ, ermC, tetK, and aacA-aphD, respectively. In 8 (25%) of all isolates had one or more staphylococcal toxin genes: the sed gene was the most frequent (12.5%), followed by eta (9.3%), tst-1 (6.25%), and sea (3.1%). In conclusion, this study highlights meat; and meat products might be reservoirs for the biofilm-producing MDR-CoNS, which harbored several toxin genes. Hence, it should not be ignored that CoNS may be related to foodborne outbreaks.

Targeting host deoxycytidine kinase mitigates Staphylococcus aureus abscess formation

Host-directed therapy (HDT) is an emerging approach to overcome antimicrobial resistance in pathogenic microorganisms. Specifically, HDT targets host-encoded factors required for pathogen replication and survival without interfering with microbial growth or metabolism, thereby eliminating the risk of resistance development. By applying HDT and a drug repurposing approach, we demonstrate that (R)-DI-87, a clinical-stage anticancer drug and potent inhibitor of mammalian deoxycytidine kinase (dCK), mitigates Staphylococcus aureus abscess formation in organ tissues upon invasive bloodstream infection. Mechanistically, (R)-DI-87 shields phagocytes from staphylococcal death-effector deoxyribonucleosides that target dCK and the mammalian purine salvage pathway-apoptosis axis. In this manner, (R)-DI-87-mediated protection of immune cells amplifies macrophage infiltration into deep-seated abscesses, a phenomenon coupled with enhanced pathogen control, ameliorated immunopathology, and reduced disease severity. Thus, pharmaceutical blockade of dCK represents an advanced anti-infective intervention strategy against which staphylococci cannot develop resistance and may help to fight fatal infectious diseases in hospitalized patients.

Bacterial diversity and resistome analysis of drinking water stored in cisterns from two First Nations communities in Manitoba, Canada

The microbiological content of water is an ongoing concern in First Nations communities in Canada. Many communities lack water treatment plants and continue to be under drinking water advisories. However, lack of access to treatment plants is only a part of the problem as poor water distribution systems also contribute to the failure to provide safe drinking water. Here, we studied the microbial diversity and antibiotic resistome from water stored in cisterns from two First Nations communities in Manitoba, Canada. We found that the cistern water contained a high number of bacteria and showed the presence of diverse antimicrobial resistance genes. Interestingly, the bacterial diversity and antimicrobial resistance genes varied considerably from that of the untreated source water, indicating that the origin of contamination in the cistern water came from within the treatment plant or along the delivery route to the homes. Our study highlights the importance of proper maintenance of the water distribution system in addition to access to water treatment facilities to ensure a supply of safe water to First Nations communities in Canada.IMPORTANCEThe work described addresses a critical issue in First Nations communities in Canada-the microbiological content of water. Many of these communities lack access to water treatment plants and frequently experience drinking water advisories. This study focused on the microbial diversity and antibiotic resistome in water stored in cisterns within two First Nations communities in Manitoba, Canada. These findings reveal that cistern water, a common source of drinking water in these communities, contains a high number of bacteria and a wide range of antimicrobial resistance genes. This highlights a serious health risk as exposure to such water can lead to the spread of drug-resistant infections, posing a threat to the well-being of the residents.

GWAS and comparative genomics reveal candidate antibiotic resistance genes in the avian pathogen Gallibacterium anatis for six widespread antibiotics

Gallibacterium anatis is a Gram-negative bacterium found in the respiratory and genital tracts of various animals, primarily poultry. Its association with septicemia and high mortality in poultry, along with the rise in multidrug-resistant strains, has amplified concerns. Recent research uncovered significant variability in antibiotic resistance profiles among G. anatis isolates from different Austrian flocks, and even between different organs within the same bird. In response, in the present study 60 of these isolates were sequenced and a combination of comparative genomics and genome-wide association study (GWAS) analysis was applied to understand the genetic variability of G. anatis across flocks and organs and to identify genes related to antibiotic resistance. The results showed that each flock harbored one or two strains of G. anatis with only a few strains shared between flocks, demonstrating a great variability among flocks. We identified genes associated with resistance to nalidixic acid, trimethoprim, cefoxitin, tetracycline, ampicillin and sulfamethoxazole. Our findings revealed that G. anatis may develop antibiotic resistance through two mechanisms: single-nucleotide mutations and the presence of specific genes that confer resistance. Unexpectedly, some tetracycline-resistant isolates lacked all known tetracycline-associated genes, suggesting the involvement of novel mechanisms of tetracycline resistance that require additional exploration. Furthermore, our functional annotation of resistance genes highlighted the citric acid cycle pathway as a potential key modulator of antibiotic resistance in G. anatis. In summary, this study describes the first application of GWAS analysis to G. anatis and provides new insights into the acquisition of multidrug resistance in this important avian pathogen.

Antibiotic resistance in livestock, environment and humans: One Health perspective

Antibiotic resistance (AR) is a complex, multifaceted global health issue that poses a serious threat to livestock, humans, and the surrounding environment. It entails several elements and numerous potential transmission routes and vehicles that contribute to its development and spread, making it a challenging issue to address. AR is regarded as an One Health issue, as it has been found that livestock, human, and environmental components, all three domains are interconnected, opening up channels for transmission of antibiotic resistant bacteria (ARB). AR has turned out to be a critical problem mainly because of the overuse and misuse of antibiotics, with the anticipation of 10 million annual AR-associated deaths by 2050. The fact that infectious diseases induced by ARB are no longer treatable with antibiotics foreshadows an uncertain future in the context of health care. Hence, the One Health approach should be emphasized to reduce the impact of AR on livestock, humans, and the environment, ensuring the longevity of the efficacy of both current and prospective antibiotics.

Review of antibiotic-resistant bacteria and antibiotic resistance genes within the one health framework

Background: The interdisciplinary One Health (OH) approach recognizes that human, animal, and environmental health are all interconnected. Its ultimate goal is to promote optimal health for all through the exploration of these relationships. Antibiotic resistance (AR) is a public health challenge that has been primarily addressed within the context of human health and clinical settings. However, it has become increasingly evident that antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) that confer resistance are transmitted and circulated within humans, animals, and the environment. Therefore, to effectively address this issue, antibiotic resistance must also be considered an environmental and livestock/wildlife problem. Objective: This review was carried out to provide a broad overview of the existence of ARB and ARGs in One Health settings. Methods: Relevant studies that placed emphasis on ARB and ARGs were reviewed and key findings were accessed that illustrate the importance of One Health as a measure to tackle growing public and environmental threats. Results: In this review, we delve into the complex interplay of the three components of OH in relation to ARB and ARGs. Antibiotics used in animal husbandry and plants to promote growth, treat, and prevent infectious diseases lead to the development of antibiotic-resistant bacteria in animals. These bacteria are transmitted from animals to humans through food and environmental exposure. The environment plays a critical role in the circulation and persistence of antibiotic-resistant bacteria and genes, posing a significant threat to human and animal health. This article also highlights how ARGs are spread in the environment through the transfer of genetic material between bacteria. This transfer can occur naturally or through human activities such as the use of antibiotics in agriculture and waste management practices. Conclusion: It is important to integrate the One Health approach into the public health system to effectively tackle the emergence and spread of ARB and genes that code for resistance to different antibiotics.

Effects of Erythromycin on Nereis succinea and the Intestinal Microbiome across Different Salinity Levels

The exposure of aquatic organisms to pollutants often occurs concomitantly with salinity fluctuations. Here, we reported the effects of erythromycin (0.250, 7.21, and 1030 μg/L) on marine invertebrate N. succinea and its intestinal microbiome under varying salinity levels (5‰, 15‰, and 30‰). The salinity elicited significant effects on the growth and intestinal microbiome of N. succinea. The susceptibility of the intestinal microbiome to erythromycin increased by 8.7- and 6.2-fold at salinities of 15‰ and 30‰, respectively, compared with that at 5‰ salinity. Erythromycin caused oxidative stress and histological changes in N. succinea intestines, and inhibited N. succinea growth in a concentration-dependent manner under 30‰ salinity with a maximum inhibition of 25%. At the intestinal microbial level, erythromycin enhanced the total cell counts at 5‰ salinity but reduced them at 15‰ salinity. Under all tested salinities, erythromycin diminished the antibiotic susceptibility of the intestinal microbiome. Two-way ANOVA revealed significant interactive effects (p < 0.05) between salinity and erythromycin on various parameters, including antibiotic susceptibility and intestinal microbial diversity. The present findings demonstrated the significant role of salinity in modulating the impacts of erythromycin, emphasizing the necessity to incorporate salinity fluctuations into environmental risk assessments.

Bioactive Compounds from Plant Origin as Natural Antimicrobial Agents for the Treatment of Wound Infections

The rising prevalence of drug-resistant bacteria underscores the need to search for innovative and nature-based solutions. One of the approaches may be the use of plants that constitute a rich source of miscellaneous compounds with a wide range of biological properties. This review explores the antimicrobial activity of seven bioactives and their possible molecular mechanisms of action. Special attention was focused on the antibacterial properties of berberine, catechin, chelerythrine, cinnamaldehyde, ellagic acid, proanthocyanidin, and sanguinarine against Staphylococcus aureus, Enterococcus spp., Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, Serratia marcescens and Pseudomonas aeruginosa. The growing interest in novel therapeutic strategies based on new plant-derived formulations was confirmed by the growing number of articles. Natural products are one of the most promising and intensively examined agents to combat the consequences of the overuse and misuse of classical antibiotics.

Synergistic horizontal transfer of antibiotic resistance genes and transposons in the infant gut microbial genome

Transposons, plasmids, bacteriophages, and other mobile genetic elements facilitate horizontal gene transfer in the gut microbiota, allowing some pathogenic bacteria to acquire antibiotic resistance genes (ARGs). Currently, the relationship between specific ARGs and specific transposons in the comprehensive infant gut microbiome has not been elucidated. In this study, ARGs and transposons were annotated from the Unified Human Gastrointestinal Genome (UHGG) and the Early-Life Gut Genomes (ELGG). Association rules mining was used to explore the association between specific ARGs and specific transposons in UHGG, and the robustness of the association rules was validated using the external database in ELGG. Our results suggested that ARGs and transposons were more likely to be relevant in infant gut microbiota compared to adult gut microbiota, and nine robust association rules were identified, among which Klebsiella pneumoniae, Enterobacter hormaechei_A, and Escherichia coli_D played important roles in this association phenomenon. The emphasis of this study is to investigate the synergistic transfer of specific ARGs and specific transposons in the infant gut microbiota, which can contribute to the study of microbial pathogenesis and the ARG dissemination dynamics.IMPORTANCEThe transfer of transposons carrying antibiotic resistance genes (ARGs) among microorganisms accelerates antibiotic resistance dissemination among infant gut microbiota. Nonetheless, it is unclear what the relationship between specific ARGs and specific transposons within the infant gut microbiota. K. pneumoniae, E. hormaechei_A, and E. coli_D were identified as key players in the nine robust association rules we discovered. Meanwhile, we found that infant gut microorganisms were more susceptible to horizontal gene transfer events about specific ARGs and specific transposons than adult gut microorganisms. These discoveries could enhance the understanding of microbial pathogenesis and the ARG dissemination dynamics within the infant gut microbiota.

Construction of a Stable Expression System Based on the Endogenous hbpB/hbpC Toxin-Antitoxin System of Halomonas bluephagenesis

Halomonas bluephagenesis is a halophilic bacterium capable of efficiently producing polyhydroxyalkanoates and other valuable chemicals through high salinity open fermentation, offering an appealing platform for next-generation industrial biotechnology. Various techniques have been developed to engineer Halomonas bluephagenesis, each with its inherent shortcomings. Genome editing methods often entail complex and time-consuming processes, while flexible expression systems relying on plasmids necessitate the use of antibiotics. In this study, we developed a stable recombinant plasmid vector, pHbPBC, based on a novel hbpB/hbpC toxin-antitoxin system found within the endogenous plasmid of Halomonas bluephagenesis. Remarkably, pHbPBC exhibited exceptional stability during 7 days of continuous subculture, eliminating the need for antibiotics or other selection pressures. This stability even rivaled genomic integration, all while achieving higher levels of heterologous expression. Our research introduces a novel approach for genetically modifying and harnessing nonmodel halophilic bacteria, contributing to the advancement of next-generation industrial biotechnology.

Resistomes in freshwater bioaerosols and their impact on drinking and recreational water safety: A perspective

Antibiotic resistance genes (ARGs) are widespread environmental pollutants of biological origin that pose a significant threat to human, animal, and plant health, as well as to ecosystems. ARGs are found in soil, water, air, and waste, and several pathways for global dissemination in the environment have been described. However, studies on airborne ARG transport through atmospheric particles are limited. The ARGs in microorganisms inhabiting an environment are referred to as the "resistome". A global search was conducted of air-resistome studies by retrieving bioaerosol ARG-related papers published in the last 30 years from PubMed. We found that there is no dedicated methodology for isolating ARGs in bioaerosols; instead, conventional methods for microbial culture and metagenomic analysis are used in combination with standard aerosol sampling techniques. There is a dearth of information on the bioaerosol resistomes of freshwater environments and their impact on freshwater sources used for drinking and recreational activities. More studies of aerobiome freshwater environments are needed to ensure the safe use of water and sanitation. In this review we outline and synthesize the few studies that address the freshwater air microbiome (from tap water, bathroom showers, rivers, lakes, and swimming pools) and their resistomes, as well as the likely impacts on drinking and recreational waters. We also discuss current knowledge gaps for the freshwater airborne resistome. This review will stimulate new investigations of the atmospheric microbiome, particularly in areas where both air and water quality are of public health concern.

Poultry manure-derived microorganisms as a reservoir and source of antibiotic resistance genes transferred to soil autochthonous microorganisms

Animal husbandry is increasing yearly due to the growing demand for meat and livestock products, among other reasons. To meet these demands, prophylactic antibiotics are used in the livestock industry (i.e., poultry farming) to promote health and stimulate animal growth. However, antibiotics are not fully metabolized by animals, and they are evacuated to the environment with excreta. Animal manure is used as fertilizer to reduce the volume of waste generated in the livestock sector. However, manure often contains microorganisms harboring antibiotic resistance genes (ARGs). Then, the microbiome of manure applicate to the soil may contribute to the spread of antibiotic resistance in the environment, including autochthonous soil-dwelling microorganisms. The present study was conducted during the crops growing season in Poland (May to September 2019) to determine the influence of poultry manure as well as poultry manure supplemented with selected antibiotics on the diversity of the soil microbiome in treatments that had not been previously fertilized with manure and the ability of antibiotic-resistant bacteria to transfer ARGs to other soil bacteria. Antibiotic concentrations were elevated at the beginning of the study and decreased over time. Poultry manure induced significant changes in the structure of microbial communities in soil; the diversity of the soil microbiome decreased, and the abundance of bacterial genera Bradyrhizobium, Streptomyces, and Pseudomonas, which are characteristic of the analyzed manure, increased. Over time, soil microbial diversity was restored to the state observed before the application of manure. Genes conferring resistance to multiple drugs as well as genes encoding resistance to bacitracin and aminoglycosides were the most frequently identified ARGs in the analyzed bacteria, including on mobile genetic elements. Multidrug resistance was observed in 17 bacterial taxa, whereas ARGs were identified in 32 bacterial taxa identified in the soil microbiome. The results of the study conclude that the application of poultry manure supplemented with antibiotics initially affects soil microbiome and resistome diversity but finally, the soil shows resilience and returns to its original state after time, with most antibiotic resistance genes disappearing. This phenomenon is of great importance in sustainable soil health after manure application.

Targeting host deoxycytidine kinase mitigates Staphylococcus aureus abscess formation

Host-directed therapy (HDT) is an emerging approach to overcome antimicrobial resistance in pathogenic microorganisms. Specifically, HDT targets host-encoded factors required for pathogen replication and survival without interfering with microbial growth or metabolism, thereby eliminating the risk of resistance development. By applying HDT and a drug repurposing approach, we demonstrate that (R)-DI-87, a clinical-stage anti-cancer drug and potent inhibitor of mammalian deoxycytidine kinase (dCK), mitigates Staphylococcus aureus abscess formation in organ tissues upon invasive bloodstream infection. Mechanistically, (R)-DI-87 shields phagocytes from staphylococcal death-effector deoxyribonucleosides that target dCK and the mammalian purine salvage pathway-apoptosis axis. In this manner, (R)-DI-87-mediated protection of immune cells amplifies macrophage infiltration into deep-seated abscesses, a phenomenon coupled with enhanced pathogen control, ameliorated immunopathology, and reduced disease severity. Thus, pharmaceutical blockade of dCK represents an advanced anti-infective intervention strategy against which staphylococci cannot develop resistance and may help to fight fatal infectious diseases in hospitalized patients.

Transmission of β-lactamases in the pork food chain: A public health concern

Antimicrobial resistance (AMR) is a risk for public health that requires management in a One Health perspective, including humans, animals, and the environment. The food production chain has been identified as a possible route of transmission of AMR bacteria to humans. The most critical issue regards resistance to the Critically Important Antimicrobials (CIAs), such as β-lactams antibiotics. Here, pigs were analysed along the entire food producing chain, including feces, carcasses and pork products (fresh meat, fermented and seasoned products) ensuring treaciability of all samples. Escherichia coli were isolated and their ability to produce ESBL and AmpC β-lactamases was evaluated both phenotypically and genotypically. Strains with the same AMR profile from feces, carcasses, and meat products were selected for phylogenetic and comparative genomic analyses to evaluate the possible "farm-to-fork" transmission of β-lactams resistant bacteria. Results showed that the percentage of ESBL strains in fecal E. coli was approximately 7% and increased slightly in the pork food chain: the 10% of ESBL E. coli isolated from carcasses and the 12.5% of isolates from fresh meat products. AmpC E. coli were found only in feces, carcasses, and fresh meat with a low prevalence. Results showed that of the 243 pigs followed along the entire food chain genetic similarities in E. coli isolated from farm-to-fork were found in only one pig (feces, carcasses and fresh meat). Frequent similarities were shown in resistant E. coli isolates from carcasses and fresh meat or fermented product (three pork food chain). Moreover, in one case, bacteria isolated from fresh meat and fermented product were genotypically similar. Concluding, direct transmission of β-lactams resistance from farm-to-fork is possible but not frequent. Further studies are needed to improve risk communication to consumers and access to clear and reliable information and health concerns on food.

Prevalence and genetic basis of tetracycline resistance in Vibrioparahaemolyticus isolates recovered from food products in Shenzhen, China during 2013 to 2021

Understanding tetracycline resistance in Vibrio parahaemolyticus from food products is crucial for effective control measures against this foodborne pathogen. This study aimed to investigate the prevalence, evolution routes, and mechanism of transmission of tetracycline resistance in Vibrio parahaemolyticus isolates collected from food products in Shenzhen, China. A total of 2342 non-duplicate Vibrio parahaemolyticus were isolated from 3509 food samples during the period 2013-2021. Among these 2342 Vibrio parahaemolyticus strains, 530 (21.37 %) were resistant to tetracycline. These tetracycline-resistant Vibrio parahaemolyticus strains were mainly isolated from shrimp samples, with the highest resistance rate (46.9 %) observed in 2019. Phylogenetic and genomic analyses of 387 isolates carrying the tet genes revealed that five different types of tet genes (tet(34), tet(A), tet(B), tet(M), and tet(E)) were present. The tet(A) gene was the most common (65 % of isolates), while tet(E) and tet(M) genes were only detected in specific years. Although tet(A) is the most commonly detected gene, it only encodes resistance in a low percentage of strains (47/129). On the other hand, the resistance rate is highest in isolates carrying tet(B) (41/55). Interestingly, V. parahaemolyticus carrying the tet genes were not necessarily tetracycline-resistant, and vice versa. A total of six different types of plasmids and two transposable units were found to carry the tet genes. V. parahaemolyticus strains that harbored these plasmids were often resistant to multiple antibiotics, indicating that horizontal transfer of antibiotic resistance genes is common among V. parahaemolyticus strains. Our findings suggest a high prevalence of tetracycline resistance in Vibrio parahaemolyticus strains recovered from food products in Shenzhen, China. These results provide valuable insight into the evolution and transmission of tetracycline resistance in foodborne Vibrio parahaemolyticus isolates and highlight the need for effective control measures to prevent the spread of antibiotic resistance.

Endophytic Bacterium Flexivirga meconopsidis sp. nov. with Plant Growth-Promoting Function, Isolated from the Seeds of Meconopsis integrifolia

Strain Q11T of an irregular coccoid Gram-positive bacterium, aerobic and non-motile, was isolated from Meconopsis integrifolia seeds. Strain Q11T grew optimally in 1% (w/v) NaCl, pH 7, at 30 °C. Strain Q11T is most closely related to Flexivirga, as evidenced by 16S rRNA gene analysis, and shares the highest similarity with Flexivirga aerilata ID2601ST (99.24%). Based on genome sequence analysis, the average nucleotide identity and digital DNA-DNA hybridization values of strains Q11T and D2601ST were 88.82% and 36.20%, respectively. Additionally, strain Q11T showed the abilities of nitrogen fixation and indole acetic acid production and was shown to promote maize growth under laboratory conditions. Its genome contains antibiotic resistance genes (the vanY gene in the vanB cluster and the vanW gene in the vanI cluster) and extreme environment tolerance genes (ectoine biosynthetic gene cluster). Shotgun proteomics also detected antibiotic resistance proteins (class A beta-lactamases, D-alanine ligase family proteins) and proteins that improve plant cold tolerance (multispecies cold shock proteins). Strain Q11T was determined to be a novel species of the genus Flexivirga, for which the name Flexivirga meconopsidis sp. nov. is proposed. The strain type is Q11T (GDMCC 1.3002T = JCM 36020 T).

Purification of aquaculture wastewater by macrophytes and biofilm systems: Efficient removal of trace antibiotics and enrichment of antibiotic resistance genes

The purification performance of aquaculture wastewater and the risk of antibiotic resistance genes (ARGs) dissemination in wetlands dominated by macrophytes remain unclear. Here, the purification effects of different macrophytes and biofilm systems on real aquaculture wastewater were investigated, as well as the distribution and abundance of ARGs. Compared to the submerged macrophytes, artificial macrophytes exhibited higher removal rates of TOC (58.80 ± 5.04 %), TN (74.50 ± 2.50 %), and TP (77.33 ± 11.66 %), and achieved approximately 79.92 % removal of accumulated trace antibiotics in the surrounding water. Additionally, the biofilm microbial communities on the surface of artificial macrophytes exhibited higher microbial diversity with fewer antibiotic-resistant bacteria (ARB) enrichment from the surrounding water. The absolute abundance of ARGs (sul1, sul2, and intI1) in the mature biofilm to be one to two orders of magnitude higher than that in the water. Although biofilms could decrease ARGs in the surrounding water by enriching ARB, the intricate network structure of biofilms further facilitated the proliferation of ARB and the dissemination of ARGs in water. Network analysis suggested that Proteobacteria and Firmicutes phyla were dominant and potential carriers of ARGs, contributing 69.00 % and 16.70 %, respectively. Our findings highlight that macrophytes and biofilm systems have great performance on aquaculture wastewater purification, but with high risk of ARGs.

The Distribution of Eight Antimicrobial Resistance Genes in Streptococcus oralis, Streptococcus sanguinis, and Streptococcus gordonii Strains Isolated from Dental Plaque as Oral Commensals

It has been proposed that oral commensal bacteria are potential reservoirs of a wide variety of antimicrobial resistance genes (ARGs) and could be the source of pathogenic bacteria; however, there is scarce information regarding this. In this study, three common streptococci of the mitis group (S. oralis, S. sanguinis, and S. gordonii) isolated from dental plaque (DP) were screened to identify if they were frequent reservoirs of specific ARGs (blaTEM, cfxA, tetM, tetW, tetQ, ermA, ermB, and ermC). DP samples were collected from 80 adults; one part of the sample was cultured, and from the other part DNA was obtained for first screening of the three streptococci species and the ARGs of interest. Selected samples were plated and colonies were selected for molecular identification. Thirty identified species were screened for the presence of the ARGs. From those selected, all of the S. sanguinis and S. oralis carried at least three, while only 30% of S. gordonii strains carried three or more. The most prevalent were tetM in 73%, and blaTEM and tetW both in 66.6%. On the other hand, ermA and cfxA were not present. Oral streptococci from the mitis group could be considered frequent reservoirs of specifically tetM, blaTEM, and tetW. In contrast, these three species appear not to be reservoirs of ermA and cfxA.

Multi-Omics Analysis of the Mechanism of Mentha Haplocalyx Briq on the Growth and Metabolic Regulation of Fattening Sheep

Mentha haplocalyx Briq (MHB) and its components have been proven to improve the growth performance of livestock and poultry. The aim of this experiment was to investigate the effects of MHB addition on growth performance, rumen and fecal microbiota, rumen fluid, serum and urine metabolism, and transcriptomics of rumen epithelial cells in meat sheep. Twelve Hu sheep were selected for the experiment and fed with basic diet (CON) and a basal diet supplemented with 80 g/kg DM of Mentha haplocalyx Briq (MHB). The experimental period was 10 weeks with the first 2 weeks as the pre-trial period. The results showed that compared with the CON group, the average daily weight gain of meat sheep in the MHB group increased by 20.1%; the total volatile fatty acid (VFA) concentration significantly increased (p < 0.05); The thickness of the cecal mucosal layer was significantly reduced (p < 0.01), while the thickness of the colonic mucosal layer was significantly increased (p < 0.05), the length of ileal villi significantly increased (p < 0.01), the thickness of colonic mucosal layer and rectal mucosal muscle layer significantly increased (p < 0.05), and the thickness of cecal mucosal layer significantly decreased (p < 0.05); The serum antioxidant capacity has increased. At the genus level, the addition of MHB changed the composition of rumen and fecal microbiota, increased the relative abundance of Paraprevotella, Alloprevotella, Marinilabilia, Saccharibacteria_genera_incertae_sedis, Subdivision5_genera_incertae_sedis and Ornatilinea in rumen microbiota, and decreased the relative abundance of Blautia (p < 0.05). The relative abundance of Prevotella, Clostridium XlVb and Parasutterella increased in fecal microbiota, while the relative abundance of Blautia and Coprococcus decreased (p < 0.05). There were significant differences in the concentrations of 105, 163, and 54 metabolites in the rumen, serum, and urine between the MHB group and the CON group (p < 0.05). The main metabolic pathways of the differences were pyrimidine metabolism, taurine and taurine metabolism, glyceride metabolism, and pentose phosphate pathway (p < 0.05), which had a significant impact on protein synthesis and energy metabolism. The transcriptome sequencing results showed that differentially expressed genes were mainly enriched in immune regulation, energy metabolism, and protein modification. Therefore, adding MHB improved the growth performance of lambs by altering rumen and intestinal microbiota, rumen, serum and urine metabolomics, and transcriptome.

Screening of Phytochemical, Antimicrobial, and Antioxidant Properties of Juncus acutus from Northeastern Morocco

Juncus acutus, acknowledged through its indigenous nomenclature "samar", is part of the Juncaceae taxonomic lineage, bearing considerable import as a botanical reservoir harboring conceivable therapeutic attributes. Its historical precedence in traditional curative methodologies for the alleviation of infections and inflammatory conditions is notable. In the purview of Eastern traditional medicine, Juncus species seeds find application for their remedial efficacy in addressing diarrhea, while the botanical fruits are subjected to infusion processes targeting the attenuation of symptoms associated with cold manifestations. The primary objective of this study was to unravel the phytochemical composition of distinct constituents within J. acutus, specifically leaves (JALE) and roots (JARE), originating from the indigenous expanse of the Nador region in northeastern Morocco. The extraction of plant constituents was executed utilizing an ethanol-based extraction protocol. The subsequent elucidation of chemical constituents embedded within the extracts was accomplished employing analytical techniques based on high-performance liquid chromatography (HPLC). For the purpose of in vitro antioxidant evaluation, a dual approach was adopted, encompassing the radical scavenging technique employing 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the total antioxidant capacity (TAC) assay. The acquired empirical data showcase substantial radical scavenging efficacy and pronounced relative antioxidant activity. Specifically, the DPPH and TAC methods yielded values of 483.45 ± 4.07 µg/mL and 54.59 ± 2.44 µg of ascorbic acid (AA)/mL, respectively, for the leaf extracts. Correspondingly, the root extracts demonstrated values of 297.03 ± 43.3 µg/mL and 65.615 ± 0.54 µg of AA/mL for the DPPH and TAC methods. In the realm of antimicrobial evaluation, the assessment of effects was undertaken through the agar well diffusion technique. The minimum inhibitory concentration, minimum bactericidal concentration, and minimum fungicidal concentration were determined for each extract. The inhibitory influence of the ethanol extracts was observed across bacterial strains including Staphylococcus aureus, Micrococcus luteus, and Pseudomonas aeruginosa, with the notable exception of Escherichia coli. However, fungal strains such as Candida glabrata and Rhodotorula glutinis exhibited comparatively lower resistance, whereas Aspergillus niger and Penicillium digitatum exhibited heightened resistance, evincing negligible antifungal activity. An anticipatory computational assessment of pharmacokinetic parameters was conducted, complemented by the application of the Pro-tox II web tool to delineate the potential toxicity profile of compounds intrinsic to the studied extracts. The culmination of these endeavors underpins the conceivable prospects of the investigated extracts as promising candidates for oral medicinal applications.

Antibiotics and their associations with antibiotic resistance genes and microbial communities in estuarine and coastal sediment of Quanzhou Bay, Southeast China

The antibiotic concentrations spanned from 11.2 to 173.8 ng/g, with quinolones and tetracyclines being observed to be prevalent. The amount of microbial biomass as determined by Phospholipid fatty acid (PLFA) ranged from 2.92 to 10.99 mg kg-1, with G- bacteria dominating. A total of 254 distinct ARGs and 10 MEGs were identified, with multidrug ARGs having the highest relative abundance (1.18 × 10-2 to 3.00 × 10-1 copies/16S rRNA gene copies), while vancomycin and sulfonamide resistance genes were the least abundant. Results from canonical-correlation analyses combined with redundancy analysis indicated that macrolides were significantly related to the shifts of microbial community structure in sediments, particularly in G+ bacteria that were more sensitive to antibiotic residues. It was observed that sulfonamide ARGs had a greater correlation with residual antibiotics than other ARGs. This study provided a field evidence that multiple residual antibiotics from coastal sites could cause fundamental shifts in microbial community and their associated ARGs.

Effects of the coexistence of antibiotics and heavy metals on the fate of antibiotic resistance genes in chicken manure and surrounding soils

Both heavy metals and antibiotics exert selection pressure on bacterial resistance, and as they are commonly co-contaminated in the environment, they may play a larger role in bacterial resistance. This study examined how breeding cycles affect antibiotic resistance genes (ARGs) in chicken manure and the surrounding topsoils at 20, 50, 100, 200, and 300 m from twelve typical laying hen farms in the Ningxia Hui Autonomous Region of northwest China. Six antibiotics, seven heavy metals, ten mobile genetic elements (MGEs), and microbial community affected the ARGs profile in chicken dung and soil samples. Tetracycline antibiotic residues were prevalent in chicken manure, as were relatively high content of aureomycin during each culture period. Zinc (Zn) content was highest among the seven heavy metals in chicken feces. Chicken dung also enriched aminoglycosides, MLSB, and tetracycline ARGs, notably during brooding and high production. The farm had a minimal influence on antibiotics in the surrounding soil, but its effect on ARGs and MGEs closer to the farm (50 m) was stronger, and several ARGs and MGEs increased with distance. Manure microbial composition differed dramatically throughout breeding cycles and sampling distances. ARGs were more strongly related with antibiotics and heavy metals in manure than soil, whereas MGEs were the reverse. Antibiotics, heavy metals, MGEs, and bacteria in manure accounted 12.28%, 22.25%, 0.74%, and 0.19% of ARGs composition variance, respectively, according to RDA and VPA. Bacteria (2.89%) and MGEs (2.82%) only affected soil ARGs composition. These findings showed that heavy metals and antibiotics are the main factors affecting faecal ARGs and bacteria and MGEs soil ARGs. This paper includes antibiotic resistance data for large-scale laying hen husbandry in northwest China and a theoretical framework for decreasing antibiotic resistance.

Tackling Drug-Resistant Tuberculosis: New Challenges from the Old Pathogen Mycobacterium tuberculosis

Antibiotics have played a crucial role in the reduction in the incidence of TB globally as evidenced by the fact that before the mid-20th century, the mortality rate within five years of the onset of the disease was 50%. The use of antibiotics has eliminated TB as a devastating disease, but the challenge of resistance to anti-TB drugs, which had already been described at the time of the introduction of streptomycin, has become a major global issue in disease management. Mismanagement of multidrug-resistant tuberculosis (MDR-TB) cases, resulting from intermittent drug use, prescription errors, and non-compliance of patients, has been identified as a critical risk factor for the development of extensively drug-resistant tuberculosis (XDR-TB). Antimicrobial resistance (AMR) in TB is a multi-factorial, complex problem of microbes evolving to escape antibiotics, the gradual decline in antibiotic development, and different economic and social conditions. In this review, we summarize recent advances in our understanding of how Mycobacterium tuberculosis evolves drug resistance. We also highlight the importance of developing shorter regimens that rapidly reach bacteria in diverse host environments, eradicating all mycobacterial populations and preventing the evolution of drug resistance. Lastly, we also emphasize that the current burden of this ancient disease is driven by a combination of complex interactions between mycobacterial and host factors, and that only a holistic approach that effectively addresses all the critical issues associated with drug resistance will limit the further spread of drug-resistant strains throughout the community.

Nanosilver: An Old Antibacterial Agent with Great Promise in the Fight against Antibiotic Resistance

Antibiotic resistance in bacteria is a major problem worldwide that costs 55 billion USD annually for extended hospitalization, resource utilization, and additional treatment expenditures in the United States. This review examines the roles and forms of silver (e.g., bulk Ag, silver salts (AgNO3), and colloidal Ag) from antiquity to the present, and its eventual incorporation as silver nanoparticles (AgNPs) in numerous antibacterial consumer products and biomedical applications. The AgNP fabrication methods, physicochemical properties, and antibacterial mechanisms in Gram-positive and Gram-negative bacterial models are covered. The emphasis is on the problematic ESKAPE pathogens and the antibiotic-resistant pathogens of the greatest human health concern according to the World Health Organization. This review delineates the differences between each bacterial model, the role of the physicochemical properties of AgNPs in the interaction with pathogens, and the subsequent damage of AgNPs and Ag+ released by AgNPs on structural cellular components. In closing, the processes of antibiotic resistance attainment and how novel AgNP-antibiotic conjugates may synergistically reduce the growth of antibiotic-resistant pathogens are presented in light of promising examples, where antibiotic efficacy alone is decreased.

Antimicrobial Peptides in Infectious Diseases and Beyond-A Narrative Review

Despite recent medical research and clinical practice developments, the development of antimicrobial resistance (AMR) significantly limits therapeutics for infectious diseases. Thus, novel treatments for infectious diseases, especially in this era of increasing AMR, are urgently needed. There is ongoing research on non-classical therapies for infectious diseases utilizing alternative antimicrobial mechanisms to fight pathogens, such as bacteriophages or antimicrobial peptides (AMPs). AMPs are evolutionarily conserved molecules naturally produced by several organisms, such as plants, insects, marine organisms, and mammals, aiming to protect the host by fighting pathogenic microorganisms. There is ongoing research regarding developing AMPs for clinical use in infectious diseases. Moreover, AMPs have several other non-medical applications in the food industry, such as preservatives, animal husbandry, plant protection, and aquaculture. This review focuses on AMPs, their origins, biology, structure, mechanisms of action, non-medical applications, and clinical applications in infectious diseases.

The Challenge of Overcoming Antibiotic Resistance in Carbapenem-Resistant Gram-Negative Bacteria: "Attack on Titan"

The global burden of bacterial resistance remains one of the most serious public health concerns. Infections caused by multidrug-resistant (MDR) bacteria in critically ill patients require immediate empirical treatment, which may not only be ineffective due to the resistance of MDR bacteria to multiple classes of antibiotics, but may also contribute to the selection and spread of antimicrobial resistance. Both the WHO and the ECDC consider carbapenem-resistant Enterobacteriaceae (CRE), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and carbapenem-resistant Acinetobacter baumannii (CRAB) to be the highest priority. The ability to form biofilm and the acquisition of multiple drug resistance genes, in particular to carbapenems, have made these pathogens particularly difficult to treat. They are a growing cause of healthcare-associated infections and a significant threat to public health, associated with a high mortality rate. Moreover, co-colonization with these pathogens in critically ill patients was found to be a significant predictor for in-hospital mortality. Importantly, they have the potential to spread resistance using mobile genetic elements. Given the current situation, it is clear that finding new ways to combat antimicrobial resistance can no longer be delayed. The aim of this review was to evaluate the literature on how these pathogens contribute to the global burden of AMR. The review also highlights the importance of the rational use of antibiotics and the need to implement antimicrobial stewardship principles to prevent the transmission of drug-resistant organisms in healthcare settings. Finally, the review discusses the advantages and limitations of alternative therapies for the treatment of infections caused by these "titans" of antibiotic resistance.