Colistin-resistant Escherichia coli carrying mcr-1 in food, water, hand rinse, and healthy human gut in Bangladesh

Fatema Tuz Johura, Jarin Tasnim, Indrajeet Barman, Sahitya Ranjan Biswas, Fatema Tuz Jubyda, Marzia Sultana, Christine Marie George, Andrew Camilli, Kimberley D. Seed, Niyaz Ahmed, Munirul Alam

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Background: One of the most significant public health concerns in today's world is the persistent upsurge of infections caused by multidrug resistant bacteria. As a result, clinicians are being forced to intervene with either less effective backup drugs or ones with substantial side-effects. Colistin is a last resort antimicrobial agent for the treatment of infections caused by multi-drug resistant gram-negative bacteria. Methods: Escherichia coli (n = 65) isolated from street food (n = 20), hand rinse (n = 15), surface water (n = 10), and healthy human stool (n = 20) were tested for colistin resistance gene mcr-1 and response to antimicrobial agents. Antimicrobial resistance genes and virulence genes were detected by employing polymerase chain reaction. DNA fingerprinting of the strains were determined by pulsed-field gel electrophoresis. Results: Screening of E. coli allowed us to confirm colistin resistance marker gene mcr-1 in 13 strains (street food, n = 4; hand rinse, n = 2; surface water, n = 4; and stool, n = 3); and two of these E. coli strains carrying mcr-1 harbored bla TEM gene encoding extended spectrum beta lactamase. Antibiotic assay results revealed all 13 E. coli strains carrying mcr-1 to be multi-drug resistant (MDR), including to colistin. The minimum inhibitory concentration (MIC) for colistin ranged from 2 to 6 μg/ml. DNA sequencing confirmed homogeneity of the nucleotide sequence for mcr-1, but the E. coli strains were heterogenous, as confirmed by pulsed-field gel electrophoresis suggesting horizontal transmission of colistin resistance in Bangladesh. Conclusion: Widespread dissemination of E. coli strains carrying mcr-1 encoding resistance to colistin in the present study is alarming as this is the last resort drug for the treatment of infections caused by MDR gram-negative bacteria resistant to almost all drugs used commonly.

Original languageEnglish (US)
Article number5
JournalGut Pathogens
Issue number1
StatePublished - Jan 27 2020


  • Colistin
  • ESBL
  • Horizontal transmission
  • Minimum inhibitory concentration (MIC)
  • Multi-drug resistant (MDR)
  • mcr-1

ASJC Scopus subject areas

  • Parasitology
  • Microbiology
  • Gastroenterology
  • Virology
  • Infectious Diseases


Dive into the research topics of 'Colistin-resistant Escherichia coli carrying mcr-1 in food, water, hand rinse, and healthy human gut in Bangladesh'. Together they form a unique fingerprint.

Cite this