Project description:Antibiotic resistance is exacerbated by the exchange of antibiotic resistance genes (ARGs) between microbes from diverse habitats. Plasmids are important ARGs mobile elements and are spread by horizontal gene transfer (HGT). In this study, we demonstrated the presence of multi-resistant plasmids from inhalable particulate matter (PM) and its effect on gene horizontal transfer. Three transferable multi-resistant plasmids were identified from PM in a hospital, using conjugative mating assays and nanopore sequencing. pTAir-3 contained 26 horizontal transfer elements and 10 ARGs. Importantly pTAir-5 harbored carbapenem resistance gene (blaOXA) which shows homology to plasmids from human and pig commensal bacteria, thus indicating that PM is a media for antibiotic resistant plasmid spread. In addition, 125 μg/mL PM2.5 and PM10 significantly increased the conjugative transfer rate by 110% and 30%, respectively, and augmented reactive oxygen species (ROS) levels. Underlying mechanisms were revealed by identifying the upregulated expressional levels of genes related to ROS, SOS, cell membranes, pilus generation, and transposition via genome-wide RNA sequencing. The study highlights the airborne spread of multi-resistant plasmids and the impact of inhalable PM on the horizontal transfer of antibiotic resistance.
2022-10-31 | GSE159850 | GEO
Project description:Bacterial Horizontal Gene Transfer in the mammalian gut
Project description:Gene transfer agents (GTAs) are prophage-like entities found in many bacterial genomes that cannot propagate themselves and instead package ~5-15 kbp fragments of the host genome that can be subsequently transferred to related recipient cells. Although suggested to facilitate horizontal gene transfer in the wild, no clear physiological role for GTAs has been elucidated. Here, we demonstrate that the a-proteobacterium Caulobacter crescentus produces bona fide GTAs. The production of Caulobacter GTAs is tightly regulated by a novel transcription factor, RogA, that represses gafYZ, which are direct activators of GTA gene transcription. Cells lacking rogA or expressing gafYZ produce GTAs harboring an ~8.3 kbp fragment of the genome that can, after cell lysis, promote transfer of DNA into recipient cells. Notably, we find that GTAs promote the survival of Caulobacter in stationary phase and following DNA damage by providing recipient cells a template for homologous recombination-based repair. This function may be broadly conserved in other GTA-producing organisms and explain the prevalence of this unusual horizontal gene transfer mechanism.
2022-04-30 | GSE184477 | GEO
Project description:Horizontal gene transfer from chloroplast to mitochondria of seagrasses
| PRJNA1159520 | ENA
Project description:Vertical and horizontal gene transfer tradeoffs direct plasmid fitness