Related Experiment Video

Updated: Mar 5, 2026

Site-specific Bacterial Chromosome Engineering: ΦC31 Integrase Mediated Cassette Exchange (IMCE)
08:21

Site-specific Bacterial Chromosome Engineering: ΦC31 Integrase Mediated Cassette Exchange (IMCE)

Published on: March 16, 2012

16.2K

Genetic Analysis of the IncX4 Plasmids: Implications for a Unique Pattern in the mcr-1 Acquisition

Jian Sun1,2, Liang-Xing Fang1,2, Zuowei Wu3

  • 1National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, People's Republic of China.

Scientific Reports
|March 25, 2017
PubMed

Insights

IncX4 plasmids carry the mcr-1 gene, a key factor in antibiotic resistance. This study identified mcr-1 on IncX4 plasmids in Enterobacteriaceae, revealing a common mechanism for its spread.

Area of Science:

  • Microbiology
  • Genetics
  • Antimicrobial Resistance

Background:

  • IncX4 plasmids are known vehicles for the spread of antimicrobial resistance genes.
  • The mcr-1 gene confers resistance to colistin, a critical last-resort antibiotic.

Purpose of the Study:

  • To screen Enterobacteriaceae isolates for IncX4 plasmids and identify those carrying the mcr-1 gene.
  • To characterize the genetic context and variability of mcr-1-positive IncX4 plasmids.

Main Methods:

  • Screening of 2,470 Enterobacteriaceae isolates.
  • High-throughput sequencing of selected plasmids.
  • Comparative genomics and PCR-RFLP analysis of variable regions.

Main Results:

  • Forty-three isolates carried IncX4 plasmids, with 13 harboring the mcr-1 gene.
  • mcr-1 was predominantly located in Variable Region I of IncX4 plasmids.
  • Nine E. coli strains possessed an epidemic pCSZ4-like IncX4 plasmid with mcr-1.
  • The insertion sequence ISApl1 was implicated in mcr-1 transposition.

Conclusions:

  • IncX4 plasmids are significant carriers of the mcr-1 gene in Enterobacteriaceae.
  • A conserved genetic context suggests a common acquisition mechanism for mcr-1.
  • Understanding these mechanisms is crucial for combating colistin resistance.

More Related Videos

Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli06:56

Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli

Published on: March 24, 2023

7.2K
Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus09:03

Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus

Published on: September 5, 2013

12.4K

Related Concept Videos

Conservative Site-specific Recombination and Phase Variation02:53

Conservative Site-specific Recombination and Phase Variation

Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
7.0K
Exon Recombination02:32

Exon Recombination

The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes. 
Exon shuffling follows “splice frame rules.” Each exon...
4.2K
X-Inactivation01:58

X-Inactivation

The human X chromosome contains over ten times the number of genes as in the Y chromosome. Since males have only one X chromosome, and females have two, one might expect females to produce twice as many of the proteins, with undesirable results.
42.8K