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Carbapenems are broad-spectrum antibiotics widely used for the treatment of human infections caused by multidrug-resistant (MDR) Gram-negative bacteria. However, emerging carbapenemase-producing Enterobacterales (CPE) are rising as a public threat to human and animal health. We screened clinical bacterial isolates from 241 dogs and 18 cats hospitalized at Veterinary Medical Teaching Hospital, Seoul National University, from 2018 to 2020 for carbapenemase production. In our study, 5 strains of metallo-β-lactamase NDM-5-producing Escherichia coli and Klebsiella pneumoniae were isolated from 4 different dogs. Multilocus sequence typing (MLST) results showed that all E. coli strains were ST410 and all K. pneumoniae strains were ST378. Whole genome analysis of the plasmid showed that bla NDM-5 is carried on a IncX3 plasmid, showing a high concordance rate with plasmids detected worldwide in human and animal isolates. The bla NDM gene was associated with the ble MBL gene and the ISAba125 element, truncated with the IS5 element. The results of this study show that CPE has already become as a threat to both animals and humans in our society, posing the necessity to solve it in terms of "One Health". Therefore, preventive strategies should be developed to prevent the spread of CPE in animal and human societies., (© 2022. The Author(s).)

Mycobacterium avium subsp. paratuberculosis (MAP) is a causative agent of Johne's disease, which is a chronic granulomatous enteropathy in ruminants. Determining the genetic diversity of MAP is necessary to understand the epidemiology and biology of MAP, as well as establishing disease control strategies. In the present study, whole genome-based alignment and comparative analysis were performed using 40 publicly available MAP genomes, including newly sequenced Korean isolates. First, whole genome-based alignment was employed to identify new genomic structures in MAP genomes. Second, the genomic diversity of the MAP population was described by pangenome analysis. A phylogenetic tree based on the core genome and pangenome showed that the MAP was differentiated into two major types (C- and S-type), which was in keeping with the findings of previous studies. However, B-type strains were discriminated from C-type strains. Finally, functional analysis of the pangenome was performed using three virulence factor databases (i.e., PATRIC, VFDB, and Victors) to predict the phenotypic diversity of MAP in terms of pathogenicity. Based on the results of the pangenome analysis, we developed a real-time PCR technique to distinguish among S-, B- and C-type strains. In conclusion, the results of our study suggest that the phenotypic differences between MAP strains can be explained by their genetic polymorphisms. These results may help to elucidate the diversity of MAP, extending from genomic features to phenotypic traits.