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Conjugal Transfer, Whole-Genome Sequencing, and Plasmid Analysis of Four mcr-1-Bearing Isolates from U.S. Patients.

ABSTRACT: Four Enterobacteriaceae clinical isolates bearing mcr-1 gene-harboring plasmids were characterized. All isolates demonstrated the ability to transfer colistin resistance to Escherichia coli; plasmids were stable in conjugants after multiple passages on nonselective media. mcr-1 was located on an IncX4 (n?=?3) or IncN (n?=?1) plasmid. The IncN plasmid harbored 13 additional antimicrobial resistance genes. Results indicate that the mcr-1-bearing plasmids in this study were highly transferable in vitro and stable in the recipients.

SUBMITTER: Zhu W

PROVIDER: S-EPMC6437532 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Conjugal Transfer, Whole-Genome Sequencing, and Plasmid Analysis of Four mcr-1-Bearing Isolates from U.S. Patients.

Zhu Wenming W Lawsin Adrian A Lindsey Rebecca L RL Batra Dhwani D Knipe Kristen K Yoo Brian B BB Perry K Allison KA Rowe Lori A LA Lonsway David D Walters Maroya S MS Rasheed J Kamile JK Halpin Alison Laufer AL

Antimicrobial agents and chemotherapy 20190327 4

Four Enterobacteriaceae clinical isolates bearing mcr-1 gene-harboring plasmids were characterized. All isolates demonstrated the ability to transfer colistin resistance to Escherichia coli; plasmids were stable in conjugants after multiple passages on nonselective media. mcr-1 was located on an IncX4 (n = 3) or IncN (n = 1) plasmid. The IncN plasmid harbored 13 additional antimicrobial resistance genes. Results indicate that the mcr-1-bearing pla ...[more]

PMID: 30745393

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Expanding landscapes of the diversified mcr-1-bearing plasmid reservoirs.

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| S-EPMC5500976 | biostudies-literature

Conjugal plasmid transfer in Streptomyces resembles bacterial chromosome segregation by FtsK/SpoIIIE.

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Horizontal transfer of a plasmid possessing mcr-1 marked with a single nucleotide mutation between Escherichia coli isolates from community residents.

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Distinct mechanisms of acquisition of mcr-1 -bearing plasmid by Salmonella strains recovered from animals and food samples.

Project description:Since the report of its discovery in E. coli in late 2015, the plasmid-mediated colistin resistance gene, mcr-1, has been detected in various bacterial species in clinical setting and various environmental niches. However, the transmission mechanisms of this gene in Salmonella is less defined. In this study, we conducted a comprehensive study to characterize the genetic features of mcr-1-positive Salmonella strains isolated from animals and foods. Our data revealed that Salmonella recovered from animals and food specimens exhibited highly different PFGE patterns, and acquired mcr-1-encoding plasmids via different mechanism. Plasmids harboring mcr-1 in Salmonella food isolates were all conjugative and similar as plasmids reported in other species of Enterobacteriaceae, whereas mcr-1-bearing plasmids from animal Salmonella isolates were not conjugative, and belonged to the IncHI2 type. The lack of a region carrying the tra genes was found to account for the inability to undergo conjugation for various sizes of IncHI2 plasmids harbored by animal strains. These data suggest that transmission of mcr-1-positive Salmonella from animal to food might not be a common event and food isolates may have acquired mcr-1-bearing plasmids from other mcr-1-positive bacteria such as E. coli, which co-exist in food samples.

| S-EPMC5643344 | biostudies-literature