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bioRxiv · 10.1101/2020.03.27.012948

Antimicrobial Resistance Profile and mcr-1 gene Detection in Salmonella Isolates from Poultry in Bangladesh: Molecular and Bioinformatics Characterization

Uddin, M. B.·Hossain, S. B.·Hasan, M.·Alam, M. N.·Debnath, M.·Begum, R.·Roy, S.·Harun-Al-Rashid, A.·Chowdhury, M. S. R.·Rahman, M. M.·Hossain, M. M.·Chowdhury, M. Y. E.·Ahmed, S. S. U.
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Abstract

Antimicrobial resistance gene mcr-1 has been disseminated globally since its first discovery in Southern China in late 2015. However, the mcr-1 gene had not been identified previously in Salmonella isolates from poultry in Bangladesh. Here, we aimed to explore antimicrobial resistance gene mcr-1 in Salmonella isolates. Eighty two Salmonella isolates were isolated and characterized from suspected poultry specimens received from different zones of the country. A phenotypic disc diffusion assay with 15 antimicrobial agents was performed following CLSI standard. The disk diffusion assay showed that, all of the isolates presented high resistance to colistin (92.68%), oxytetracycline (86.59%), co-trimoxazole (76.83%), ciprofloxacin (73.17%) and enrofloxacin (65.85%). Further, randomly selected 10 Salmonella isolates were analyzed by polymerase chain reaction (PCR) targeting genus-specific invA and antimicrobial (colistin) resistance mcr-1 genes. Five were confirmed for the presence of the mcr-1 gene belonging to Salmonella spp. Further, sequencing followed by phylogenetic analysis revealed divergent evolutionary relation between the LptA and MCR proteins rendering them resistant to colistin. Three-dimensional homology structures of MCR-1 proteins were constructed and verified using different bioinformatics tools. Moreover, molecular docking interactions suggested that, MCR-1 and LptA share a similar substrate binding cavity which could be validated for the functional analysis. The results represent here is the first molecular and in silico analysis of colistin resistance mcr-1 gene of Salmonella in poultry in Bangladesh, which may emphasize the importance of the study on antibiotic resistance genes requiring for national monitoring and strategic surveillance in the country.

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Uddin, M. B., Hossain, S. B., Hasan, M., Alam, M. N., Debnath, M., Begum, R., Roy, S., Harun-Al-Rashid, A., Chowdhury, M. S. R., Rahman, M. M., Hossain, M. M., Chowdhury, M. Y. E., Ahmed, S. S. U.. 2020-03-29. Antimicrobial Resistance Profile and mcr-1 gene Detection in Salmonella Isolates from Poultry in Bangladesh: Molecular and Bioinformatics Characterization. https://doi.org/10.1101/2020.03.27.012948

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