Global distribution and genomic characteristics analysis of avian-derived mcr-1-positive Escherichia coli

The mcr-1 gene has emerged as a hot topic in the field of public health in recent years. It is a plasmid-mediated colistin resistance gene that was first discovered in humans and pigs in China and has since been reported in multiple countries and regions around the world. The presence of the mcr-1 gene signifies that bacteria have developed resistance to polymyxin drugs, which are considered the last resort for treating multidrug-resistant Gram-negative bacterial infections. Therefore, the spread of the mcr-1 gene could pose a serious threat to global public health. Poultry, as a major component of livestock trade, plays a significant role in the dissemination of resistance genes. To fill the gap in the genomic analysis of avian-derived mcr-1-positive Escherichia coli on a global scale, we selected 1,104 high-quality mcr-1-positive genomic data from the NCBI Pathogen Database. Additionally, we employed various bioinformatics analysis methods to elucidate the geographical distribution and genomic characteristics of mcr-1 E. coli derived from poultry worldwide. The study results indicate that mcr-1-positive E. coli are widely distributed in China and European countries, with chickens serving as the primary host. mcr-1-positive E. coli from different countries exhibit a high degree of genetic similarity, among which ST10 E. coli is the main carrier of the mcr-1 gene. The transposon Tn6330 is a key facilitator of mcr-1 dissemination, while IncI2 and IncX4 are the main plasmid types carrying the mcr-1 gene. The related research has been published in the journal Ecotoxicology and Environmental Safety under the title "Global distribution and genomic characteristics analysis of avian-derived mcr-1-positive Escherichia coli," and is accessible at the following DOI: https://doi.org/10.1016/j.ecoenv.2024.117109.