Genomic analysis of a novel phage vB_SenS_ST1UNAM with lytic activity against Salmonella enterica serotypes.

In this study, we present the complete annotated genome of a novel Salmonella phage, vB_SenS_ST1UNAM. This phage exhibits lytic activity against several Salmonella enterica serotypes, such as S. Typhi, S. Enteritidis, and S. Typhimurium strains, which are major causes of foodborne illness worldwide. Its genome consists of a linear, double-stranded DNA of 47,877 bp with an average G+C content of 46.6%. A total of 85 coding regions (CDS) were predicted, of which only 43 CDS were functionally assigned. Neither genes involved in the regulation of lysogeny, nor antibiotic resistance genes were identified. This phage harbors a lytic cassette that encodes a type II-holin and a Rz/Rz1-like spanin complex, along with a restriction-modification evasion system and a depolymerase that degrades Salmonella exopolysaccharide. Moreover, the comparative analysis with closely related phage genomes revealed that vB_SenS_ST1UNAM represents a novel genus, for which the genus "Gomezvirus" within the subfamily "ST1UNAM-like" is proposed.

Molecular typification of Escherichia coli from community-acquired urinary tract infections in Mexico.

One hundred and five uropathogenic Escherichia coli (UPEC) strains from patients with community-acquired urinary tract infections were characterized according to phylogenetic group, virulence factors, serogroup, antibiotic resistance, and genotype. The pathogenic phylogenetic groups (B2, D, and F) were found in 71.4% of the tested strains. Among them, the main uropathogenic serogroups were O8, O25, and O75, in which 97.1% of the strains had a multidrug-resistant profile. Sixteen virulence genes were analysed using a combination of polymerase chain reaction (PCR) assays, with the fimH, irp-2, iutA, aer, iucC, PAI, sat, iroN, usp, and cnf1 genes being mainly found in pathogenic phylogroups. The E. coli O25b-ST131 clone was identified in 32% of the strains assigned to the pathogenic phylogroup B2. These findings demonstrate that virulence genes encoding adhesin components, iron-acquisition systems, toxins, and pathogenicity-associated islands were highly prevalent among the pathogenic phylogroup of UPEC strains.

Does phage-mediated horizontal gene transfer represent an environmental risk?

A growing number of recent studies suggest that the contribution of phages to antibiotic resistance should not be underestimated. Here we describe their implications for public and environmental health, with a special emphasis on the mechanisms underlying phage-mediated horizontal gene transfer.

Phage therapy for urinary tract infections: does it really work? / Terapia de fagos para infecciones del tracto urinario: ¿realmente funciona?

Although phage therapy is still in the research and development stage, there are already a small number of cases where phages have been successfully used as an alternative treatment for multidrug-resistant infections. Given this, this Commentary discusses the potential contribution of phage therapy to combat urinary tract infections.(AU)

Genomic characterization of two bacteriophages (vB_EcoS-phiEc3 and vB_EcoS-phiEc4) belonging to the genus Kagunavirus with lytic activity against uropathogenic Escherichia coli.

In this study, the genomes of two lytic bacteriophages, vB_EcoS-phiEc3 and vB_EcoS-phiEc4, were sequenced and characterized using bioinformatics approaches. Whole-genome analysis showed that both phages belonged to the Kagunavirus genus, Guernseyvirinae subfamily and Siphoviridae family. Moreover, their genomes had 45, 288 bp and 44,540 bp, and G + C content of 48.42% and 50.04%, respectively. The genome of vB_EcoS-phiEc3 harbored 80 protein coding sequences (CDSs), whereas vB_EcoS-phiEc4 harbored 75 CDSs. Among them, 50 CDSs in vB_EcoS-phiEc3 and 44 CDSs in vB_EcoS-phiEc4 were considered as functional genes. Their lytic activity against multidrug-resistant uropathogenic Escherichia coli (UPEC) strains, as well as the absence of antibiotic resistance genes, lysogenic and virulence genes, enable vB_EcoS-phiEc3 and vB_EcoS-phiEc4 as a safe therapy option against UPEC infections.

Phage therapy for urinary tract infections: does it really work?

Although phage therapy is still in the research and development stage, there are already a small number of cases where phages have been successfully used as an alternative treatment for multidrug-resistant infections. Given this, this Commentary discusses the potential contribution of phage therapy to combat urinary tract infections.

Genome analysis of a new Escherichia phage vB_EcoM_C2-3 with lytic activity against multidrug-resistant Escherichia coli.

In this study, we present the complete, annotated genome of a new member of the Tequatrovirus (T4-like) genus, Escherichia phage vB_EcoM_C2-3. This phage has an isometric head (92 nm in diameter) and a contractile tail (114 nm in length). Its genome consists of a linear, double-stranded DNA of 167,069bp with an average G+C content of 35.3%. There are 267 predicted genes, of which 125 encode functional proteins, including those for DNA replication, transcription and packaging, phage morphogenesis and cell lysis. Neither genes involved in the regulation of lysogeny nor antibiotic resistance genes were identified. Based on our results, its genomic features provide valuable insights into the use of a potential biocontrol agent, as Escherichia phage vB_EcoM_C2-3 exhibited lytic activity against E. coli, including multidrug-resistant strains.

Identification and characterization of class 1 integrons among multidrug-resistant uropathogenic Escherichia coli strains in Mexico.

This study aimed to identify and characterize integrons among multidrug-resistant (MDR) uropathogenic Escherichia coli (UPEC) from outpatients in Mexico City, Mexico. PCR assays were used to screen for the presence of class 1, 2 and 3 integrons, whose PCR products were sequenced to identify the inserted gene cassettes within the variable regions. Out of 83 tested strains, 53 (63.9%) were positive for the presence of class 1 integrons, whereas no integrons were detected in the remaining strains, regardless of their classes. Most of the strains carrying the intI1 gene belonged to the extraintestinal B2 (41.5%) and commensal A (32.1%) phylogroups, and to a lesser extent, the extraintestinal D (20.8%) and commensal B1 (5.7%) phylogroups. Moreover, 8 different gene cassette arrangements were detected, with dfrA17 and aadA5 being the most common (32.1% of the class 1 integron-positive strains), which confer resistance to trimethoprim/sulfamethoxazole and aminoglycosides, respectively. Our results suggest that class 1 integrons are widely distributed among MDR-UPEC strains in Mexico, which may directly or indirectly contribute to the selection of MDR strains. These findings are important for a better understanding of the factors and mechanisms that promote multidrug resistance among UPEC strains.

Making waves: How does the emergence of antimicrobial resistance affect policymaking?

This article considers current trends in antimicrobial resistance (AMR) research and knowledge gaps relevant to policymaking in the water sector. Specifically, biological indicators of AMR (antibiotic-resistant bacteria and their resistance genes) and detection methods that have been used so far are identified and discussed, as well as the problems with and solutions to the collection of AMR data, sewage surveillance lessons from the COVID-19 pandemic, and the financial burden caused by AMR, which could be synergically used to improve advocacy on AMR issues in the water sector. Finally, this article proposes solutions to overcoming existing hurdles and shortening the time it will take to have an impact on policymaking and regulation in the sector.

|Isolation and characterization of novel bacteriophages as a potential therapeutic option for Escherichia coli urinary tract infections.

Urinary tract infections (UTIs) are mainly caused by uropathogenic Escherichia coli (UPEC), whose impact can be exacerbated by multidrug-resistant (MDR) strains. Effective control strategies are, therefore, urgently needed. Among them, phage therapy represents a suitable alternative. Here, we describe the isolation and characterization of novel phages from wastewater samples, as well as their lytic activity against biofilm and adherence of UPEC to HEp-2 cells. The results demonstrated that phage vB_EcoM-phiEc1 (ϕEc1) belongs to Myoviridae family, whereas vB_EcoS-phiEc3 (ϕEc3) and vB_EcoS-phiEc4 (ϕEc4) belong to Siphoviridae family. Phages showed lytic activity against UPEC and gut commensal strains. Phage ϕEc1 lysed UPEC serogroups, whereas phages ϕEc3 and ϕEc4 lysed only UTI strains with higher prevalence toward the O25 serogroup. Moreover, phages ϕEc1 and ϕEc3 decreased both biofilm formation and adherence, whereas ϕEc4 was able to decrease adherence but not biofilm formation. In conclusion, these novel phages showed the ability to decrease biofilm and bacterial adherence, making them promising candidates for effective adjuvant treatment against UTIs caused by MDR UPEC strains. KEY POINTS: Phage with lytic activity against MDR UPEC strains were isolated and characterized under in vitro conditions. A novel method was proposed to evaluate phage activity against bacterial adherence in HEp-2 cell.. Phages represent a suitable strategy to control infections caused by MDR bacteria.

Characterization of auto-agglutinating and non-typeable uropathogenic Escherichia coli strains.

INTRODUCTION: Uropathogenic Escherichia coli (UPEC) are the main etiological agent of urinary tract infections (UTIs). Association between different serotypes and UTIs is known, however, some strains are incapable to be serotyped. The aim of this work was to study bthe phenotypical and genotypical characteristics of 113 non-typeable (NT) and auto-agglutinating (AA) E. coli strains, isolated from UTIs in children and adults. METHODOLOGY: The 113 UPEC strains were analyzed by PCR assays using specific primers to determine their serogroups, fimH, papC, iutA, sat, hlyCA and cnf1, virulence associated genes, and chuA, yjaA and TSPE4.C2 for phylogroup determination. Additionally, the diffusion disk method was performed to evaluate the antimicrobial resistance to 18 antimicrobial agents. RESULTS: Using the PCR assay, 63% (71) of the strains were genotyped showing O25 and O75 as the most common serogroups. The virulence genes fimH (86%) and iutA (74%) were the most prevalent, in relation to the phylogroups the commensal (A and B1) and virulent (B2 and D) showed similar frequencies (P > 0.05). The antimicrobial susceptibility test showed a high percentage (73%) of multidrug-resistant strains. CONCLUSIONS: The genotyping allowed identifying the serogroup in many of the strains that could not be typed by traditional serology. The strains carried virulence genes and were multidrug-resistant in both, commensal and virulent phylogroups. Our findings revealed that, in addition to the classical UPEC serogroups, there are pathogenic serogroups not reported yet.

Relación entre factores de virulencia, resistencia a antibióticos y los grupos filogenéticos de Escherichia coli uropatógena en dos localidades de México / Relationship between virulence factors, resistance to antibiotics and phylogenetic groups of uropathogenic Escherichia coli in two locations in Mexico

Introducción: Escherichia coli es el principal agente causal de infecciones del tracto urinario (ITU), y sus factores de virulencia son los responsables de la gravedad de estas infecciones emergentes. El objetivo de este estudio fue evaluar la relación entre los determinantes de virulencia y susceptibilidad a antibióticos con los grupos filogenéticos de E.coli aisladas de ITU en 2 localidades de México. Métodos: Se analizaron 50 aislamientos de E.coli de una localidad en el centro del país y 57 provenientes de una localidad al suroeste. Los aislamientos fueron caracterizados fenotípica (serotipificación, ensayos de adherencia, formación de biopelícula, producción de hemolisina y susceptibilidad antibióticos) y genotípicamente (grupos filogenéticos y genes de virulencia). Resultados: Los grupos filogenéticos B2 (60%) y F (12%) fueron significativamente predominantes en la localidad del centro con mayor frecuencia de los genes fimH (96%), iutA (66%) y sat (36%) en comparación con la localidad en el suroeste, donde los grupos A (35%) y B1 (21%) fueron más frecuentes y presentaron menor cantidad de genes de virulencia. El 21,5% del total de aislamientos pertenecieron al grupo O25-ST131. La producción de hemolisina y biopelícula fue significativamente mayor en cepas de la localidad del sureste. La resistencia a ampicilina (92,5%), tetraciclina (76,6%) y trimetoprim/sulfametoxazol (70,1%) fueron las más comunes en ambos grupos. Conclusión: El grupo filogenético, los factores de virulencia y la susceptibilidad a antibióticas de E.colicausante de ITU en la comunidad varían significativamente entre las poblaciones mexicanas estudiadas. Los grupos filogenéticos A y B1 pueden ser multirresistentes y tienen la capacidad de producir infecciones urinarias (AU)

Introduction: Escherichia coli is the major causative agent of urinary tract infections (UTI), and virulence factors are responsible for the severity of these emerging infections. The aim of this study was to evaluate the relationship between virulence determinants and antibiotic susceptibility with phylogenetic groups of E.coli isolates of UTI in two locations in Mexico. Methods: An analysis was performed on 50 isolates of E.coli from the centre of the country and 57 from a town in the southwest. The isolates were characterized by phenotype (serotyping assays, in vitro adhesion, biofilm formation, production of haemolysin, and antibiotic susceptibility) and genotype (phylogenetic groups and virulence genes). Results: In the centre of the country location the phylogenetic group B2 (60%) and F (12%) were significantly more prevalent and had a higher frequency of genes, fimH (96%), iutA (66%), sat(36%), compared to the southwest location, where the group A (35%) and B1 (21%) were significantly predominant and had fewer virulence genes. About one-fifth (21.5%) of all isolates belonged to the O25-ST131 group. Haemolysin and biofilm producing strains were significantly higher in the southwest location. Resistance to ampicillin (92.5%), tetracycline (76.6%), and trimethoprim/sulfamethoxazole (70.1%) were the most common in both groups. Conclusion: The phylogenetic group, virulence factors, and antibiotic susceptibility of the E.coli that causes UTI in the community, varies significantly among the Mexican populations studied. Phylogenetic groups A and B1 may be multidrug resistant and have the ability to produce UTI (AU)

Relationship between virulence factors, resistance to antibiotics and phylogenetic groups of uropathogenic Escherichia coli in two locations in Mexico. / Relación entre factores de virulencia, resistencia a antibióticos y los grupos filogenéticos de Escherichia coli uropatógena en dos localidades de México.

INTRODUCTION: Escherichia coli is the major causative agent of urinary tract infections (UTI), and virulence factors are responsible for the severity of these emerging infections. The aim of this study was to evaluate the relationship between virulence determinants and antibiotic susceptibility with phylogenetic groups of E.coli isolates of UTI in two locations in Mexico. METHODS: An analysis was performed on 50 isolates of E.coli from the centre of the country and 57 from a town in the southwest. The isolates were characterized by phenotype (serotyping assays, in vitro adhesion, biofilm formation, production of haemolysin, and antibiotic susceptibility) and genotype (phylogenetic groups and virulence genes). RESULTS: In the centre of the country location the phylogenetic group B2 (60%) and F (12%) were significantly more prevalent and had a higher frequency of genes, fimH (96%), iutA (66%), sat (36%), compared to the southwest location, where the group A (35%) and B1 (21%) were significantly predominant and had fewer virulence genes. About one-fifth (21.5%) of all isolates belonged to the O25-ST131 group. Haemolysin and biofilm producing strains were significantly higher in the southwest location. Resistance to ampicillin (92.5%), tetracycline (76.6%), and trimethoprim/sulfamethoxazole (70.1%) were the most common in both groups. CONCLUSION: The phylogenetic group, virulence factors, and antibiotic susceptibility of the E.coli that causes UTI in the community, varies significantly among the Mexican populations studied. Phylogenetic groups A and B1 may be multidrug resistant and have the ability to produce UTI.