SEARCH · PubMed Health

Results for “Neomycin”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

5 recordsLinked to original sources

PubMed2024

Intranasal neomycin evokes broad-spectrum antiviral immunity in the upper respiratory tract.

Respiratory virus infections in humans cause a broad-spectrum of diseases that result in substantial morbidity and mortality annually worldwide. To reduce the global burden of respiratory viral diseases, preventative and therapeutic interventions that are accessible and effective are urgently needed, especially in countries that are disproportionately affected. Repurposing generic medicine has the potential to bring new treatments for infectious diseases to patients efficiently and equitably. In this study, we found that intranasal delivery of neomycin, a generic aminoglycoside antibiotic, induces the expression of interferon-stimulated genes (ISGs) in the nasal mucosa that is independent of the commensal microbiota. Prophylactic or therapeutic administration of neomycin provided significant protection against upper respiratory infection and lethal disease in a mouse model of COVID-19. Furthermore, neomycin treatment protected Mx1 congenic mice from upper and lower respiratory infections with a highly virulent strain of influenza A virus. In Syrian hamsters, neomycin treatment potently mitigated contact transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In healthy humans, intranasal application of neomycin-containing Neosporin ointment was well tolerated and effective at inducing ISG expression in the nose in a subset of participants. These findings suggest that neomycin has the potential to be harnessed as a host-directed antiviral strategy for the prevention and treatment of respiratory viral infections.

Animals↗

PubMed2025

The aphA1 kanamycin and neomycin resistance gene originated in Klebsiella michiganensis.

BACKGROUND: The origins of several antibiotic resistance genes have been traced to intrinsic genes present in bacterial chromosomes. The aphA1 gene, which confers resistance to the aminoglycosides kanamycin and neomycin, is commonly found in diverse Gram-negative bacterial pathogens, and is associated with several different mobile genetic elements. However, its origin had not been identified. OBJECTIVES: To determine whether the aphA1-containing segments in novel compound and pseudo-compound transposons found in three historic plasmids, pIE545, R478 and Rts1, are found in the chromosome of a specific bacterial species. METHODS: Passenger segments of transposons containing the aphA1 gene were compared to one another and to chromosomal sequences in GenBank using BLAST. RESULTS: In pIE545, aphA1 is in a 5424 bp compound transposon, TnaphA1-pIE545, that is bounded by directly oriented copies of IS102. The 3.3 kb aphA1-containing passenger segment is >99% identical to a contiguous part of several Klebsiella michiganensis chromosomes. The 4.3 kb aphA1-containing segment of the IS26-bounded pseudo-compound transposon PTnaphA1-R478 in R478 is also >99% identical to a contiguous part of several K. michiganensis chromosomes that differ in the gene content surrounding aphA1. The 2.2 kb passenger segment of the IS26-bounded PTn2680 from Rts1 arose via a third independent acquisition from a K. michiganensis chromosome. CONCLUSIONS: The aphA1 gene has been captured and mobilized on at least three occasions from K. michiganensis chromosomes with related but distinct surrounding configurations.

DNA Transposable Elements↗

PubMed2025

CRISPR/Cas9-compatible plasmids enabling seven dominant genetic selection methods for the human fungal pathogen Cryptococcus neoformans.

Cryptococcus neoformans is the most common cause of human fungal meningitis and an important model system for studying fundamental eukaryotic biology. Genetic manipulation of this organism relies on three dominant drug resistance markers (nourseothricin acetyltransferase [NAT], neomycin phosphotransferase II [NEO], and hygromycin B phosphotransferase [HYG]) and the recyclable dominant prototrophic marker amdS. With ongoing technological advances that are expanding our ability to explore cryptococcal gene function, contemporary studies often require multiple genetic manipulations in the same strain. Additional dominant selection methods would maximize the utility of these tools by facilitating their combinatorial use. Here, we identify blasticidin S resistance via the blasticidin S deaminase (BSD) or blasticidin S resistance (BSR) markers as a novel dominant selection method for C. neoformans. We further validate phleomycin resistance via the bleomycin resistance gene (BLE) marker as an additional selection method, confirming a study that first established this marker 25 years ago (J. Hua, J. D. Meyer, and J. K. Lodge, Clin Diagn Lab Immunol 7:125-128, 2000, https://doi.org/10.1128/cdli.7.1.125-128.2000). To enable highly efficient CRISPR/Cas9-mediated genome modification, we incorporated these markers, as well as the newly established dominant prototrophic marker ptxD (M. Khongthongdam, T. Phetruen, and S. Chanarat, Microbiol Spectr 13:e01618-24, 2025, https://doi.org/10.1128/spectrum.01618-24), into a vector series that enables the construction of fused marker-sgRNA products via PCR. Altogether, this work expands the number of dominant genetic selection methods for C. neoformans to seven, including five drug selection regimes and two prototrophic methods. The vector series has been deposited at Addgene. IMPORTANCE Cryptococcus neoformans is the top-ranked World Health Organization priority fungal pathogen due to its widespread distribution and inadequate treatment options. Additionally, as a basidiomycete yeast occupying an underexplored branch of the fungal kingdom, this organism is a powerful system for deciphering core eukaryotic biology that is absent in classic model fungi. Defining functions for novel cryptococcal genes is a crucial priority, and the availability of additional genetic selection methods would facilitate these efforts. In this study, we establish blasticidin S resistance as a novel genetic selection method for C. neoformans, and we validate a previous report using phleomycin resistance as such. This work expands the number of reliable dominant selection methods to seven, providing flexibility for the introduction of sequential genetic modifications into single strains.

Cryptococcus neoformans↗

PubMed2026

Antimicrobial susceptibility patterns of commensal fecal bacteria isolated from pigs with an intentional genomic alteration that included the selectable marker gene nptII.

INTRODUCTION: Animals with intentional genomic alterations (IGAs) hold promise for meeting increasing worldwide demand for animal-source proteins. As part of regulatory risk assessment for introducing animals with IGAs into the food chain, monitoring commensal bacterial microbiota is recommended due to concern that antimicrobial resistance genes used during IGA selection could be transferred, via horizontal gene transfer, to gastrointestinal or environmental bacterial populations, potentially contributing to antimicrobial resistance. The objective of this study was to assess the antimicrobial susceptibility patterns in commensal bacteria isolated from fecal samples of GalSafe™ pigs that have an IGA that includes the aminoglycoside resistance gene nptII. METHODS: Antimicrobial resistance rates observed in Escherichia coli, Salmonella, Campylobacter and Enterococcus isolated from GalSafe™ pigs were compared to resistance rates observed in conventional pigs at slaughter. Bacterial isolates were tested for antimicrobial resistance genes by PCR and one isolate underwent whole genome sequencing. RESULTS: In total, 137 bacterial isolates recovered from 55 fecal samples collected from 47 individual adult GalSafe™ pigs were evaluated. Prevalence of antimicrobial resistance in GalSafe™ pigs was generally similar to, or lower than, resistance prevalence reported from conventional pigs at slaughter, based on National Antimicrobial Resistance Monitoring System (NARMS) data. Higher resistance rates in GalSafe™ pigs were observed only for quinolones in Campylobacter coli (ciprofloxacin and nalidixic acid) and nitrofurantoin in Enterococcus spp. One isolate (E. coli) was positive for nptII neomycin resistance gene, the same gene used for IGA selection in GalSafe™ pigs, and the remaining 136 isolates were negative for nptII. However, the positive isolate did not appear to contain nptII derived from the GalSafe™ pig genome as the sequences flanking the gene did not match the IGA. DISCUSSION: We did not detect evidence of nptII gene transformation into bacterial species of potential human health importance in this population of GalSafe™ pigs.

NARMS↗

PubMed2026

First Report and Integrated Characterization of Aeromonas veronii Associated with the Protected Fish Diptychus maculatus in Xinjiang, China.

Aeromonas veronii is a widely distributed opportunistic aquatic pathogen associated with diseases in freshwater fish. Despite the ecological and conservation significance of Diptychus maculatus, a protected cold-water fish inhabiting high-altitude ecosystems, information regarding its associated bacterial communities remains limited. This study aimed to isolate and characterize A. veronii recovered from D. maculatus and provide baseline information on its occurrence and phenotypic characteristics. Eight bacterial isolates were recovered from various tissues, including skin, gills, eye, intestine, dorsal fin, body kidney, gonad, and spleen of randomly sampled fish individuals from Xinjiang, China. Phenotypic and biochemical characterization, together with 16S rRNA sequencing, supported their identification as A. veronii, while gyrB analysis of a representative isolate provided additional species-level confirmation. Antimicrobial susceptibility testing revealed a consistent multidrug-resistance phenotype among all isolates. The isolates were susceptible to enrofloxacin, cefotaxime, ceftriaxone, and florfenicol. Intermediate responses were observed for ciprofloxacin, ofloxacin, doxycycline, oxytetracycline, and trimethoprim-sulfamethoxazole, whereas resistance was detected against norfloxacin, neomycin, penicillin, amoxicillin, tetracycline, and erythromycin. In vitro biofilm assays demonstrated weak to moderate biofilm-forming capacity among isolates. These findings provide baseline data for wildlife microbial surveillance and conservation-oriented monitoring of protected fish populations, supporting future investigations into environmental monitoring, genomic characterization, and host-microbe interactions.

Aeromonas veronii↗