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Background: Klebsiella pneumoniae species complex (KpSC) is an important disseminator of carbapenemase‐encoding genes, mainly blaKPC‐2 and blaNDM‐1, from hospitals to the environment. Consequently, carbapenem‐resistant strains can be spread through the agrifood system, raising concerns about food safety. This study therefore aimed to isolate carbapenem‐resistant KpSC strains from the agricultural and environmental sectors and characterize them using phenotypic, molecular, and genomic analyses. Results: Klebsiella pneumoniae and Klebsiella quasipneumoniae strains isolated from soils used for lemon, guava, and fig cultivation, and from surface waters, displayed an extensive drug‐resistance profile and carried blaKPC‐2, blaNDM‐1, or both. In addition to carbapenemase‐encoding genes, KpSC strains harbor a broad resistome (antimicrobial resistance and metal tolerance) and present putative hypervirulence. Soil‐derived K. pneumoniae strains were assigned as high‐risk clones (ST11 and ST307) and harbored the blaKPC‐2 gene associated with Tn4401b and Tn3‐like elements on IncN‐pST15 and IncX5 plasmids. In surface waters, the coexistence of blaKPC‐2 and blaNDM‐1 genes was identified in K. pneumoniae ST6326, a new carbapenem‐resistant regional Brazilian clone. In this case, blaKPC‐2 with Tn4401a isoform and blaNDM‐1 associated with a Tn125‐like transposon were located on different plasmids. Klebsiella quasipneumoniae ST526 also presented the blaNDM‐1 gene associated with a Tn3000 transposon on an IncX3 plasmid. Conclusion: These findings provide a warning regarding the transmission of carbapenemase‐positive KpSC across the agricultural and environmental sectors, raising critical food safety and environmental issues. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Bacterial resistance occurs by spontaneous mutations or horizontal gene transfer mediated by mobile genetic elements, which represents a great concern. Resistance to β-lactam antibiotics is mainly due to the production of β-lactamases, and an important mechanism of fluoroquinolone resistance is the acquisition plasmid determinants. The aim of this study was to verify the presence of β-lactamase-encoding genes and plasmid-mediated quinolone resistance genes in different water samples obtained from São Paulo state, Brazil. A high level of these resistance genes was detected, being the blaSHV, blaGES, and qnr the most prevalent. Besides that, the blaNDM gene, which codify an important and hazardous metallo-β-lactamase, was detected. [ABSTRACT FROM AUTHOR]

The mcr-type gene encodes the main plasmid-mediated mechanism of colistin resistance and has been reported in several bacterial species obtained from different sources. Anthropogenic activities in the environment favor the evolution of antimicrobial resistance. Indeed, mcr-1-positive Escherichia coli strains were susceptible to non-polymyxins antimicrobials, but now emerging as multidrug-resistant (MDR) lineages. In this regard, hundreds of surface water and agricultural soil samples were screened for the presence of E. coli carrying the mcr-type genes and mcr-1-positive strains were subjected to in-depth genomic analysis. Almost all colistin-resistant strains were classified as MDR, highlighting those obtained from soils that showed resistance to extended-spectrum cephalosporins and carbapenems. International and high-risk clones of E. coli were identified, with ST10 and ST1720 shared between water and soil samples. Resistome analysis showed a broad resistome (AMR, metal tolerance, and biocide resistance). The mcr-1.1 and mcr-1.26 allelic variants were detected on IncX4 and IncI2 plasmids. Curiously, mcr-1-positive E. coli strains from agricultural soils harbored plasmid-mediated bla CTX-M-1 , bla CTX-M-8 , or bla KPC-2 genes. Virulome analysis demonstrated traits of a high putative virulence potential, with the presence of extraintestinal pathogenic E. coli. Comparative analysis revealed the persistence and dissemination of plasmid-mediated antimicrobial resistance genes in genetically diversity E. coli strains at the human-animal-environmental interface. These findings demonstrate a possible emerging AMR trend with the convergence of resistance to colistin and broad-spectrum β-lactams in environmental-derived E. coli strains., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The rapid dissemination of colistin resistance mcr-type genes and extended-spectrum β-lactamase-encoding genes at the human-animal-environment interface has raised concerns worldwide. In this study, we performed a genomic investigation of a multidrug (MDR)- and colistin-resistant Escherichia coli strain recovered from an urban stream strongly affected by pollution and used for recreational purposes in Brazil. E. coli strain EW827 was resistant to clinically significant antimicrobials, including polymyxins, extended-spectrum cephalosporins, and fluoroquinolones. Whole-genome sequencing analysis revealed that EW827 strain belonged to ST1775 and carried the fimH137 allele, clinically relevant antimicrobial resistance genes (e.g., mcr-1.1, bla CTX-M-2 , and bla CMY-2 ), tolerance genes to metals, and biocide resistance genes. Moreover, IncX4 and IncI1-ST12 replicon types were identified carrying mcr-1.1 and bla CMY-2 , respectively. A novel genetic environment of the mcr-1.1 gene, in which a 258-bp ∆IS5-like was inserted in the opposite orientation upstream of the mcr-1.1-pap2 element, was also detected. Additionally, the bla CTX-M-2 gene was harbored by a Tn21-like element on the chromosome. The occurrence of MDR E. coli co-harboring mcr-1.1, bla CTX-M-2 , and bla CMY-2 in urban water represents a potential risk to humans, animals, and environmental safety. Therefore, epidemiological studies are required to monitoring multidrug-resistant bacteria and their antimicrobial resistance genes in aquatic ecosystems to determine possible routes and fates of these genes., (Copyright © 2021. Published by Elsevier B.V.)

Bacterial resistance occurs by spontaneous mutations or horizontal gene transfer mediated by mobile genetic elements, which represents a great concern. Resistance to β-lactam antibiotics is mainly due to the production of β-lactamases, and an important mechanism of fluoroquinolone resistance is the acquisition plasmid determinants. The aim of this study was to verify the presence of β-lactamase-encoding genes and plasmid-mediated quinolone resistance genes in different water samples obtained from São Paulo state, Brazil. A high level of these resistance genes was detected, being the bla SHV , bla GES , and qnr the most prevalent. Besides that, the bla NDM gene, which codify an important and hazardous metallo-β-lactamase, was detected.