TY - JOUR

T1 - Genomic Characterization of mcr-1-Carrying Foodborne Salmonella enterica serovar Typhimurium and Identification of a Transferable Plasmid Carrying mcr-1, blaCTX-M-14, qnrS2, and oqxAB Genes From Ready-to-Eat Pork Product in China

AU - Li, Lili

AU - Wan, Xiulin

AU - Olsen, Rikke Heidemann

AU - Xiao, Jian

AU - Wang, Chong

AU - Xu, Xuebin

AU - Meng, Hecheng

AU - Shi, Lei

N1 - Publisher Copyright: Copyright © 2022 Li, Wan, Olsen, Xiao, Wang, Xu, Meng and Shi.

PY - 2022

Y1 - 2022

N2 - Salmonella enterica resistant to colistin, third-generation cephalosporins (3GCs), and fluoroquinolones (FQs) has been deemed a high-priority pathogen by the World Health Organization (WHO). The objective of this study was to characterize 11 mcr-1-harboring Salmonella enterica serovar Typhimurium isolates from raw pork and ready-to-eat (RTE) pork products in Guangzhou, China. All isolates were multi-drug resistant and contained 6–24 antibiotic-resistant genes. The mcr-1 gene was localized in the most conserved structure (mcr-1-orf) in eight isolates and in mobile structure (ISApl1-mcr-1-orf) in three isolates. One raw pork isolate SH16SF0850, co-harbored mcr-1, blaCTX−M−14, and oqxAB genes. One isolate 17Sal008 carried mcr-1, blaCTX−M−14, qnrS2, and oqxAB genes located on a 298,622 bp IncHI2 plasmid pSal008, which was obtained from an RTE pork product for the first time. The pSal008 was closely related to a plasmid in an S. typhimurium isolate from a 1-year-old diarrheal outpatient in China and was found to be transferable to Escherichia coli J53 by conjugation. Genome sequence comparisons by core-genome Multi Locus Sequence Typing (cgMLST) based on all S. typhimurium isolates from China inferred highly probably epidemiological links between selected pork isolates and no possible epidemiologically links between RTE pork isolate 17Sal008 and other isolates. Our findings indicate that raw pork and pork products are potential reservoirs of mcr-1-harboring S. typhimurium and highlight the necessity for continuous monitoring of colistin, 3GCs, and FQs resistant S. typhimurium from different origins.

AB - Salmonella enterica resistant to colistin, third-generation cephalosporins (3GCs), and fluoroquinolones (FQs) has been deemed a high-priority pathogen by the World Health Organization (WHO). The objective of this study was to characterize 11 mcr-1-harboring Salmonella enterica serovar Typhimurium isolates from raw pork and ready-to-eat (RTE) pork products in Guangzhou, China. All isolates were multi-drug resistant and contained 6–24 antibiotic-resistant genes. The mcr-1 gene was localized in the most conserved structure (mcr-1-orf) in eight isolates and in mobile structure (ISApl1-mcr-1-orf) in three isolates. One raw pork isolate SH16SF0850, co-harbored mcr-1, blaCTX−M−14, and oqxAB genes. One isolate 17Sal008 carried mcr-1, blaCTX−M−14, qnrS2, and oqxAB genes located on a 298,622 bp IncHI2 plasmid pSal008, which was obtained from an RTE pork product for the first time. The pSal008 was closely related to a plasmid in an S. typhimurium isolate from a 1-year-old diarrheal outpatient in China and was found to be transferable to Escherichia coli J53 by conjugation. Genome sequence comparisons by core-genome Multi Locus Sequence Typing (cgMLST) based on all S. typhimurium isolates from China inferred highly probably epidemiological links between selected pork isolates and no possible epidemiologically links between RTE pork isolate 17Sal008 and other isolates. Our findings indicate that raw pork and pork products are potential reservoirs of mcr-1-harboring S. typhimurium and highlight the necessity for continuous monitoring of colistin, 3GCs, and FQs resistant S. typhimurium from different origins.

KW - ESBLs

KW - FQs

KW - mcr-1

KW - ready-to-eat pork product

KW - S. typhimurium

U2 - 10.3389/fmicb.2022.903268

DO - 10.3389/fmicb.2022.903268

M3 - Journal article

C2 - 35847096

AN - SCOPUS:85134157807

VL - 13

JO - Frontiers in Microbiology

JF - Frontiers in Microbiology

SN - 1664-302X

M1 - 903268

ER -