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Reyes, J.

Publications and source records attributed to Reyes, J..

2 recordsLinked to original sources

Diverse Escherichia coli lineages, from domestic animals and humans in a household, carry colistin resistance gene mcr-1 in Ecuador

The aim of this study was to investigate the presence of Escherichia coli carrying mcr-1 gene in domestic animals close to a child who suffered a peritoneal infection by a mcr-1 positive E. coli. Rectal or cloacal swabs and fecal samples from domestic animals were plated on selective media to isolate colistin-resistant E. coli and isolates were submitted to detection of mcr-1 gene, pulsed field gel electrophoresis (PFGE), multi-locus sequence typing (MLST), replicon typing and S1-PFGE. Four mcr-1 positive E. coli isolates (from chicken, turkey and dog) were recovered. No shared PFGE pattern or MLST sequence type were observed among isolates. A 60Kb IncI1{gamma} mcr-1-carrying plasmid was detected in all isolates. Our results suggest that mcr-1 gene was horizontally disseminated amongst different lineages of E. coli from domestic animals in the childs household.\n\nImportanceHorizontally transferable colistin resistance (mcr-1 gene) is thought to have originated in domestic animals and transferred to humans through meat and dairy products. In the present report we show evidence that the mcr-1 gene could be transferred to different E. coli strains colonizing different hosts (humans and pets) in the same household.

microbiology

A Cell Type-Specific Class of Chromatin Loops Anchored at Large DNA Methylation Nadirs

Higher order chromatin structure and DNA methylation are implicated in multiple developmental processes, but their relationship to cell state is unknown. Here, we found that large (~10kb) DNA methylation nadirs can form long loops connecting anchor loci that may be dozens of megabases apart, as well as interchromosomal links. The interacting loci comprise ~3.5Mb of the human genome. The data are more consistent with the formation of these loops by phase separation of the interacting loci to form a genomic subcompartment, rather than with CTCF-mediated extrusion. Interestingly, unlike previously characterized genomic subcompartments, this subcompartment is only present in particular cell types, such as stem and progenitor cells. Further, we identify one particular loop anchor that is functionally associated with maintenance of the hematopoietic stem cell state. Our work reveals that H3K27me3-marked large DNA methylation nadirs represent a novel set of very long-range loops and links associated with cellular identity.\n\nSummaryHi-C and DNA methylation analyses reveal novel chromatin loops between distant sites implicated in stem and progenitor cell function.

genomics