The emergence of antibiotic resistance has raised serious concerns within scientific and medical communities, and has underlined the importance of developing new antimicrobial agents to combat such infections. Bacteriophages, naturally occurring bacterial viruses, have long been characterized as promising antibiotic alternatives. Although bacteriophages hold great promise as medical tools, clinical applications have been limited by certain characteristics of phage biology, with structural fragility under the high temperatures and acidic environments of therapeutic applications significantly limiting therapeutic effectiveness. This study presents and evaluates the efficacy of a new accelerated evolution platform, chemically accelerated viral evolution (CAVE), which provides an effective and robust method for the rapid enhancement of desired bacteriophage characteristics. Here, our initial use of this methodology demonstrates its ability to confer significant improvements in phage thermal stability. Analysis of the mutation patterns that arise through CAVE iterations elucidates the manner in which specific genetic modifications bring forth desired changes in functionality, thereby providing a roadmap for bacteriophage engineering.

Urinary tract infections (UTIs) are a common human infection. Antibiotic resistance in extended-spectrum β-lactamase (ESBL)-producing uropathogenic E. coli (UPEC) is a major therapeutic challenge due to limited treatment alternatives. The aim was to characterize the antimicrobial resistance (AMR) and dynamics of ESBL-producing UPEC isolates from UTI cases seen at a local hospital in Cusco, Peru. Ninety-nine isolates from respective patients were characterized against 18 different antibiotics. Latent class analysis (LCA) was used to evaluate the dynamics across the study time according to resistance patterns. The median age of patients was 51 years old, and nearly half were women. ESBL-producing UPEC isolates were slightly more frequent in outpatient services than emergency rooms, and there were higher resistance rates in males compared to females. Half of the ESBL producers were resistant to aminoglycosides and nitrofurantoin. Cefoxitin and fosfomycin resistance was 29.3% and 14.1%, respectively. Resistance to carbapenems was not observed. All isolates were multidrug-resistant bacteria, and 16.2% (16/99) were also classified as extensively drug-resistant bacteria. The resistance patterns varied across the study time and differed regarding sex and healthcare service. The study revealed high levels of AMR to commonly used antimicrobials and a dynamic circulation of ESBL-producing UPEC isolates with varying resistance patterns.

We present here the draft genome sequence of the first New Delhi metallo-β-lactamase (NDM-1)-producing Escherichia coli strain, belonging to sequence type 155 (ST155), isolated in Peru. Assembly of this draft genome resulted in 5,061,184 bp, revealing a clinically significant resistome for β-lactams, aminoglycosides, tetracyclines, phenicols, sulfonamides, trimethoprim, and fluoroquinolones.

Salmonella enterica is a Gram-negative bacterium, recognized as one of the most important foodborne pathogens in the world. Bacteriophages represent a promising alternative to the biocontrol of Salmonella . Here, we report the isolation of five Salmonella bacteriophages, the sequencing of their full genomes, and initial genomic characterization.

El metomilo es un compuesto químico inhibidor de la acetilcolinesterasa que actúa por contacto sistémico y es uno de los agroquímicos de mayor uso como insecticida-acaricida para el control de un amplio rango de plagas agrícolas. El siguiente trabajo tiene como objetivo evaluar la toxicidad aguda del metomilo sobre el pez introducido Poecilia latipinna (Lesueur 1821) (Poecilidae) a 2, 4, 6, 8, 24, 48, 72 y 96 h de exposición. Los bioensayos se realizaron con cinco concentraciones y cuatro repeticiones. La temperatura fue de 21,8 oC ± 1, pH 7,34 ± 0,31, conductividad eléctrica 0,54 mS ± 0,03; y un promedio de solutos disueltos en el medio de 267,39 mg.L-1. Los datos obtenidos durante las pruebas se evaluaron utilizando el método estadístico analítico Probit ver. 1,5. Los resultados obtenidos de la Concentración Letal media (CL ) del metomilo sobre P. latipinna fueron: 2 h = 13,95 mg IA.L-1, 4 h = 10,39 mg IA.L-1, 6 50 h = 8,12 mg IA.L-1, 8 h = 5,81 mg IA. L-1, 24 h = 3,99 mg IA.L-1, a 48 h = 2,61 mg IA.L-1, a 72 h = 2,24 mg IA.L-1 y finalmente a 96 h = 2,08 IA.L mg-1. A la concentración más alta se observó un cambio de intensidad de color de la piel de plateado a negro.