Detection of the colistin-resistant mcr-1 gene in escherichia coli isolates in retail pork from fresh markets in Bangkok, Thailand

Abstract

This study aimed to investigate the presence of colistin resistance (the mcr-1 gene) in E. coli isolates in retail pork. A total of 900 retail pork samples were collected from 36 fresh markets in Bangkok from January to October 2018. We collected E. coli that were isolated from MacConkey agar and Eosin Methylene Blue agar and screened the presence of the mcr-1 gene by using PCR. Results showed the MICs to Colistin of the 900 studied isolates, colistin resistance (MIC ï ³ 2 mg/l) was identified in 9.44% (85/900) confirmed E. coli isolates. The size of the mcr-1 amplicon was 309 bp. The mcr-1 gene was detected in 37.65% (32/85) samples. The highest frequency was observed in the mcr-1 genes from Thawi Watthana (75.00%). The data demonstrated that the mcr-1 gene was highly prevalent in retail pork purchased from the fresh market