Convergence of mcr-1 and broad-spectrum ß-lactamase genes in Escherichia coli strains from the environmental sector.

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 blaCTX-M-1, blaCTX-M-8, or blaKPC-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 ß-lactams in environmental-derived E. coli strains.

The detection of KPC-2, NDM-1, and VIM-2 carbapenemases in international clones isolated from fresh vegetables highlights an emerging food safety issue.

Resistance to carbapenems emerged in clinical settings and has rapidly spread to other sectors, such as food and the environment, representing a One Health problem. In this regard, vegetables contaminated by critical priority pathogens have raised global concerns. Here, we have performed a whole-genome sequence-based analysis of extensively drug-resistant Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa strains isolated from cabbage, spinach, and lettuce, respectively. Genomic analysis revealed the emergence of international and high-risk clones belonging to ST340, ST155, and ST233, harboring a broad resistome to clinically important antimicrobials. In this context, K. pneumoniae, E. coli, and P. aeruginosa strains carried blaKPC-2, blaNDM-1, and blaVIM-2, respectively. The blaKPC-2 gene with a non-Tn4401 element (NTEKPC-Ic) was located on an IncX3-IncU plasmid, while the blaVIM-2 gene was associated with a Tn402-like class 1 integron, In559, on the chromosome. Curiously, the blaNDM-1 gene coexisted with the blaPER-2 gene on an IncC plasmid and the regions harboring both genes contained sequences of Tn3-like element ISKox2-like family transposase. Comparative genomic analysis showed interspecies and clonal transmission of carbapenemase-encoding genes at the human-animal-environmental interface. These findings raise a food safety alert about hospital-associated carbapenemase producers, supporting that fresh vegetables can act as a vehicle for the spread of high-risk clones.

The relationship between water quality and the microbial virulome and resistome in urban streams in Brazil.

Urban streams that receive untreated domestic and hospital waste can transmit infectious diseases and spread drug residues, including antimicrobials, which can then increase the selection of antimicrobial-resistant bacteria. Here, water samples were collected from three different urban streams in the state of São Paulo, Brazil, to relate their range of Water Quality Indices (WQIs) to the diversity and composition of aquatic microbial taxa, virulence genes (virulome), and antimicrobial resistance determinants (resistome), all assessed using untargeted metagenome sequencing. There was a predominance of phyla Proteobacteria, Actinobacteria, and Bacteroidetes in all samples, and Pseudomonas was the most abundant detected genus. Virulence genes associated with motility, adherence, and secretion systems were highly abundant and mainly associated with Pseudomonas aeruginosa. Furthermore, some opportunistic pathogenic genera had negative correlations with WQI. Many clinically relevant antimicrobial resistance genes (ARGs) and efflux pump-encoding genes that confer resistance to critically important antimicrobials were detected. The highest relative abundances of ARGs were ß-lactams and macrolide-lincosamide-streptogramin. No statistically supported relationship was detected between the abundance of virulome/resistome and collection type/WQI. On the other hand, total solids were a weak predictor of gene abundance patterns. These results provide insights into various microbial outcomes given urban stream quality and point to its ecological complexity. In addition, this study suggests potential consequences for human health as mediated by aquatic microbial communities responding to typical urban outputs.

Klebsiella quasipneumoniae subsp. similipneumoniae ST1859 O5:KL35 from Soil: First Report of qnrE1 in the Environment.

A Klebsiella quasipneumoniae subsp. similipneumoniae strain, named S915, belonging to the ST1859 O5:KL35, and harboring the plasmid-mediated quinolone resistance qnrE1 gene, was isolated from a soil sample cultivated with lettuce in Brazil. The core genome multilocus sequence typing analysis revealed that S915 strain was most related to a clinical strain of Brazil. Comparative genomic analysis showed that ST1859 O5:KL35 strains have been circulating in clinical settings and are closely related to multidrug resistance and multimetal tolerance. Strain S915 presented a plasmid contig co-harboring the qnrE1 gene and tellurite tolerance operon. The region harboring the qnrE1 gene (ISEcp1-qnrE1-araJ-ahp) shared high similarity with others from infected humans, ready-to-eat dish, and food-producing animals in Brazil. This is the first report of the plasmid-mediated qnrE1 gene in the environment. Our findings evidence the initial dissemination of the qnrE1 gene in the environment by the introduction of a clinical strain, which may be spread to different sectors, representing a One Health challenge.

Genetic plurality of blaKPC-2-harboring plasmids in high-risk clones of Klebsiella pneumoniae of environmental origin.

International high-risk clones of Klebsiella pneumoniae are important human pathogens that are spreading to the environment. In the COVID-19 pandemic scenario, the frequency of carbapenemase-producing strains increased, which can contribute to the contamination of the environment, impacting the surrounding and associated ecosystems. In this regard, KPC-producing strains were recovered from aquatic ecosystems located in commercial, industrial, or agricultural areas and were submitted to whole-genome characterization. K. pneumoniae and Klebsiella quasipneumoniae subsp. quasipneumoniae strains were assigned to high-risk clones (ST11, ST340, ST307) and the new ST6325. Virulome analysis showed genes related to putative hypervirulence. Strains were resistant to almost all antimicrobials tested, being classified as extensively drug-resistant or multidrug-resistant. In this context, a broad resistome (clinically important antimicrobials and hazardous metal) was detected. Single replicon (IncX5, IncN-pST15, IncU) and multireplicon [IncFII(K1)/IncFIB(pQil), IncFIA(HI1)/IncR] plasmids were identified carrying the blaKPC-2 gene with Tn4401 and non-Tn4401 elements. An unusual association of blaKPC-2 and qnrVC1 and the coexistence of blaKPC-2 and mer operon (mercury tolerance) was found. Comparative analysis revealed that blaKPC-2-bearing plasmids were most similar to plasmids from Enterobacterales of Brazil, China, and the United States, evidencing the long persistence of plasmids at the human-animal-environmental interface. Furthermore, the presence of uncommon plasmids, displaying the interspecies, intraspecies, and clonal transmission, was highlighted. These findings alert for the spread of high-risk clones producing blaKPC-2 in the environmental sector and call attention to rapid dispersion in a post-pandemic world.

Phylogeographical Landscape of Citrobacter portucalensis Carrying Clinically Relevant Resistomes.

During a surveillance study conducted to assess the occurrence and genomic landscape of critical priority pathogens circulating at the human-animal-environment interface in Brazil, as part of the Grand Challenges Explorations-New Approaches to Characterize the Global Burden of Antimicrobial Resistance program, two multidrug-resistant (MDR) Citrobacter portucalensis carrying blaCTX-M-15 extended-spectrum ß-lactamase (ESBL) genes, isolated from green sea turtles, were characterized. Genomic and phylogeographical analysis of C. portucalensis genomes available in public databases revealed the intercontinental dissemination of clades carrying different arrays of clinically relevant genes conferring resistance to carbapenems, broad-spectrum cephalosporins, cephamycins, aminoglycosides and fluoroquinolones, disinfectants, and heavy metals. Our observations suggest that C. portucalensis could be emerging as critical priority bacteria of both public and One Health importance worldwide. IMPORTANCE The global spread of antibiotic-resistant priority pathogens beyond the hospital setting is a critical issue within a One Health context that integrates the human-animal-environment interfaces. On the other hand, next-generation sequencing technologies along with user-friendly and high-quality bioinformatics tools have improved the identification of bacterial species, and bacterial resistance surveillance. The novel Citrobacter portucalensis species was proposed in 2017 after taxonomic reclassification and definition of the strain A60T isolated in 2008. Here, we presented genomic data showing the occurrence of multidrug-resistant C. portucalensis isolates carrying blaCTX-M-15 ESBL genes in South America. Additionally, we observed the intercontinental dissemination of clades harboring a broad resistome to clinically relevant antibiotics. Therefore, these findings highlight that C. portucalensis is a global MDR bacteria that carries intrinsic blaCMY- and qnrB-type genes and has become a critical priority pathogen due to the acquisition of clinically relevant resistance determinants, such as ESBL and carbapenemase-encoding genes.

Colistin-resistant mcr-1-positive Escherichia coli ST1775-H137 co-harboring blaCTX-M-2 and blaCMY-2 recovered from an urban stream.

The rapid dissemination of colistin resistance mcr-type genes and extended-spectrum ß-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, blaCTX-M-2, and blaCMY-2), tolerance genes to metals, and biocide resistance genes. Moreover, IncX4 and IncI1-ST12 replicon types were identified carrying mcr-1.1 and blaCMY-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 blaCTX-M-2 gene was harbored by a Tn21-like element on the chromosome. The occurrence of MDR E. coli co-harboring mcr-1.1, blaCTX-M-2, and blaCMY-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.

Multidrug resistance IncC plasmid carrying blaCMY-97 in Shiga toxin-producing Escherichia coli ST215-H54 of ovine origin.

CMY-type ß-lactamases are the most reported plasmid-mediated AmpC (pAmpC), with the CMY-2-like group being the most clinically relevant described in Escherichia coli at human-animal-environment interface. Shiga toxin-producing E. coli (STEC) lineages are zoonotic pathogens commonly reported causing serious clinical conditions in humans, including severe diarrheagenic diseases. Therefore, this study aimed to investigate a multidrug-resistant (MDR) STEC isolate (A313) recovered from a healthy sheep and carrying mobile blaCMY-97, that encodes a pAmpC belonging to the CMY-2-like group. The A313 isolate exhibited a MDR profile to clinically relevant antimicrobials (i.e., cephalosporins, aminoglycosides, and fluoroquinolones), but reduced susceptibility to extended-spectrum cephalosporins and aztreonam. Besides, virulence genes (stx2, gad and iutA) were detected in A313, which belonged to ST215/CC10 and phylogenetic group A, whereas the fimH54 was identified. The blaCMY-97 gene and other antimicrobial resistance determinants [aph(6)-Id, aph(3″)-Ib, aac(3)-IId, aadA5, floR, tetA, sul1, and sul2], as well as genes encoding tolerance to mercury (merRTPCADE), were harbored by an IncC plasmid (named pA313-CMY-97, ~ 176 kb). A novel genetic context of blaCMY-2-like, in which a 208-bp ISEcp1 was truncated by an IS26 in the opposite orientation upstream of the blaCMY-97 gene (IS26-∆ISEcp1-blaCMY-97-blc-sugE-encR), was also identified in pA313-CMY-97. To the best of our knowledge, this is the first report on the acquisition of blaCMY-97 into a plasmid. Therefore, we reported ovine as reservoir of clinically relevant MDR bacteria carrying mobile blaCMY-97 with potential for zoonotic transmission.

Appearance of mcr-9, blaKPC, cfr and other clinically relevant antimicrobial resistance genes in recreation waters and sands from urban beaches, Brazil.

The co-occurrence of mcr-like and carbapenemase-encoding genes have been reported mainly in humans and animals, whereas, in the environment, studies are gradually increasing due to the One Health approach. In this study, we investigated antimicrobial resistance genes (ARGs) in water and sand samples from marine environments in Brazil. Total DNA from 56 samples (33 sands and 23 waters) was obtained and 27 different ARGs were detected, highlighting the presence of mcr-9, blaKPC and cfr genes. Additionally, the microbiological analysis revealed that sand samples of all analyzed beaches were not recommended for primary use, whereas water samples from most beaches were classified as unsuitable for bathing. The presence of clinically relevant ARGs in urban beaches suggests the presence of antimicrobial-resistant bacteria. Furthermore, to the best of our knowledge, this is the first report of mcr-9 and cfr genes in the environment from Brazil and recreational areas worldwide.

Whole-genome sequence-based analysis of the Paenibacillus aquistagni strain DK1, a polyethylene-degrading bacterium isolated from landfill.

Polyethylene-degrading bacteria have been emerging as a rational and safe alternative in bioremediation strategies. In this context, some Paenibacillus species produce enzymes involved in the biodegradation of pollutants. Among the enzymes involved in the biodegradation of polyethylene, the alkane hydroxylases, encoded by alkB homologous genes, play a key role in this process. Therefore, this study aimed to identify and perform a genomic investigation of the first polyethylene-degrading Paenibacillus sp. strain, named DK1. The whole-genome sequence-based analysis revealed that the DK1 strain belonged to the species Paenibacillus aquistagni and shared a total of 4327 CDSs with P. aquistagni strain 11. On the other hand, a comparison of the gene clusters showed that DK1 strain harbored a genetic context surrounding the alkB-like gene similar to that found in Pseudomonas sp. strains. The percentage of similarity ranged from 47.88 to 99.76% among all complete amino acid sequences of AlkB-like proteins analyzed. Nevertheless, the predicted amino acid sequences of AlkB-like contained typical structural motifs of alkane hydroxylases, such as His boxes and the HYG motif. These findings associated with the previously reported phenotypic results highlighted the potential of P. aquistagni strain DK1 to biodegrade polyethylene. Therefore, further studies focusing on the biochemical and structural properties of the AlkB-like protein from Paenibacillus may also contribute to the development of sustainable bioremediation strategies.

Colistin-Resistant mcr-1-Positive Escherichia coli ST131-H22 Carrying bla CTX-M-15 and qnrB19 in Agricultural Soil.

The pandemic Escherichia coli sequence type 131 (ST131) carrying plasmid-mediated colistin resistance mcr genes has emerged worldwide causing extraintestinal infections, with lineages belonging to three major clades (A, B, and C). Clade B is the most prevalent in animals, contaminating associated meat products, and can be transmitted zoonotically. However, the bla CTX-M-15 gene has only been associated with C2 subclade so far. In this study, we performed a genomic investigation of an E. coli (strain S802) isolated from a kale crop in Brazil, which exhibited a multidrug-resistant (MDR) profile to clinically significant antimicrobials (i.e., polymyxin, broad-spectrum cephalosporins, aminoglycosides, and fluoroquinolones). Whole-genome sequencing analysis revealed that the S802 strain belonged to serotype O25:H4, ST131/CC131, phylogenetic group B2, and virotype D5. Furthermore, S802 carried the clade B-associated fimH22 allele, genes encoding resistance to clinically important antimicrobials, metals, and biocides, and was phylogenetically related to human, avian, and swine ST131-H22 strains. Additionally, IncHI2-IncQ1, IncF [F2:A-:B1], and ColE1-like plasmids were identified harboring mcr-1.1, bla CTX-M-15, and qnrB19, respectively. The emergence of the E. coli ST131-H22 sublineage carrying mcr-1.1, bla CTX-M-15, and qnrB19 in agricultural soil represents a threat to food and environmental safety. Therefore, a One Health approach to genomic surveillance studies is required to effectively detect and limit the spread of antimicrobial-resistant bacteria and their resistance genes.

Correction: Class 1 integron-borne cassettes harboring blaCARB-2 gene in multidrug-resistant and virulent Salmonella Typhimurium ST19 strains recovered from clinical human stool samples, United States.

[This corrects the article DOI: 10.1371/journal.pone.0240978.].

Endophytic Lifestyle of Global Clones of Extended-Spectrum ß-Lactamase-Producing Priority Pathogens in Fresh Vegetables: a Trojan Horse Strategy Favoring Human Colonization?

The global spread of antibiotic-resistant bacteria and their resistance genes is a critical issue that is no longer restricted to hospital settings, but also represents a growing problem involving environmental and food safety. In this study, we have performed a microbiological and genomic investigation of critical priority pathogens resistant to broad-spectrum cephalosporins and showing endophytic lifestyles in fresh vegetables sold in a country with high endemicity of extended-spectrum ß-lactamases (ESBLs). We report the isolation of international high-risk clones of CTX-M-15-producing Escherichia coli, belonging to clonal complexes CC38 and CC648, and Klebsiella pneumoniae of complex CC307 from macerated tissue of surface-sterilized leaves of spinach, cabbage, arugula, and lettuce. Regardless of species, all ESBL-positive isolates were able to endophytically colonize common bean (Phaseolus vulgaris) seedlings, showed resistance to acid pH, and had a multidrug-resistant (MDR) profile to clinically relevant antibiotics (i.e., broad-spectrum cephalosporins, aminoglycosides, and fluoroquinolones). Genomic analysis of CTX-M-producing endophytic Enterobacterales revealed a wide resistome (antibiotics, biocides, disinfectants, and pesticides) and virulome, and genes for endophytic fitness and for withstanding acidic conditions. Transferable IncFIB and IncHI2A plasmids carried bla CTX-M-15 genes and, additionally, an IncFIB plasmid (named pKP301cro) also harbored genes encoding resistance to heavy metals. These data support the hypothesis that fresh vegetables marketed for consumption can act as a figurative Trojan horse for the hidden spread of international clones of critical WHO priority pathogens producing ESBLs, and/or their resistance genes, to humans and other animals, which is a critical issue within a food safety and broader public and environmental health perspective.IMPORTANCE Extended-spectrum ß-lactamases (ESBL)-producing Enterobacterales are a leading cause of human and animal infections, being classified as critical priority pathogens by the World Health Organization. Epidemiological studies have shown that spread of ESBL-producing bacteria is not a problem restricted to hospitals, but also represents a growing problem involving environmental and food safety. In this regard, CTX-M-type ß-lactamases have become the most widely distributed and clinically relevant ESBLs worldwide. Here, we have investigated the occurrence and genomic features of ESBL-producing Enterobacterales in surface-sterilized fresh vegetables. We have uncovered that international high-risk clones of CTX-M-15-producing Escherichia coli and Klebsiella pneumoniae harboring a wide resistome and virulome, carry additional genes for endophytic fitness and resistance to acidic conditions. Furthermore, we have demonstrated that these CTX-M-15-positive isolates are able to endophytically colonize plant tissues. Therefore, we believe that fresh vegetables can act as a figurative Trojan horse for the hidden spread of critical priority pathogens exhibiting endophytic lifestyles.

Hypermucoviscous/hypervirulent and extensively drug-resistant QnrB2-, QnrS1-, and CTX-M-3-coproducing Klebsiella pneumoniae ST2121 isolated from an infected elephant (Loxodonta africana).

The rapid dissemination of extended-spectrum ß-lactamases (ESBLs)-producing Enterobacterales from different spheres worldwide over recent years has become a serious problem in both human and veterinary medicine. CTX-M-3-type ESBL has only been reported on few occasions, and in Brazil the blaCTX-M-3 gene has been identified only once in clinical strains. In this study, we aimed to molecularly characterize a hypermucoviscous (hm), hypervirulent (hv), and extensively drug-resistant (XDR) Klebsiella pneumoniae strain isolated from a lung tissue culture of an infected elephant. The A246 strain belonged to ST2121 and presented hm phenotype, hypervirulence-associated genes, and carried blaCTX-M-3 and plasmid-mediated quinolone resistance genes (qnrB2 and qnrS1) on an IncFII-IncQ1-IncM1 multireplicon plasmid (pA246-CTX-M-3, ∼ 162 kb). A novel genetic context of blaCTX-M-3, in which a 482-bp ISEcp1 was truncated by an IS26, was also harbored by pA246-CTX-M-3. Furthermore, in vivo experiments revealed that the hm/hv A246 strain killed 100 % of the Galleria mellonella larvae at 72 h post-infection. Our findings evidence the intercontinental dissemination of a rare K. pneumoniae ST2121 and the multidrug resistance IncFII-IncQ1-IncM1 plasmid. Therefore, to the best of our knowledge, this is the first report of an XDR K. pneumoniae coproducing CTX-M-3, QnrB2, and QnrS1 isolated from captive wild animals.

Class 1 integron-borne cassettes harboring blaCARB-2 gene in multidrug-resistant and virulent Salmonella Typhimurium ST19 strains recovered from clinical human stool samples, United States.

International lineages, such as Salmonella Typhimurium sequence type (ST) 19, are most often associated with foodborne diseases and deaths in humans. In this study, we compared the whole-genome sequences of five S. Typhimurium strains belonging to ST19 recovered from clinical human stool samples in North Carolina, United States. Overall, S. Typhimurium strains displayed multidrug-resistant profile, being resistance to critically and highly important antimicrobials including ampicillin, ticarcillin/clavulanic acid, streptomycin and sulfisoxazole, chloramphenicol, tetracycline, respectively. Interestingly, all S. Typhimurium strains carried class 1 integron (intl1) and we were able to describe two genomic regions surrounding blaCARB-2 gene, size 4,062 bp and 4,422 bp for S. Typhimurium strains (HS5344, HS5437, and HS5478) and (HS5302 and HS5368), respectively. Genomic analysis for antimicrobial resistome confirmed the presence of clinically important genes, including blaCARB-2, aac(6')-Iaa, aadA2b, sul1, tetG, floR, and biocide resistance genes (qacEΔ1). S. Typhimurium strains harbored IncFIB plasmid containing spvRABCD operon, as well as rck and pef virulence genes, which constitute an important apparatus for spreading the virulence plasmid. In addition, we identified several virulence genes, chromosomally located, while the phylogenetic analysis revealed clonal relatedness among these strains with S. enterica isolated from human and non-human sources obtained in European and Asian countries. Our results provide new insights into this unusual class 1 integron in virulent S. Typhimurium strains that harbors a pool of genes acting as potential hotspots for horizontal gene transfer providing readily adaptation to new surrounds, as well as being crucially required for virulence in vivo. Therefore, continuous genomic surveillance is an important tool for safeguarding human health.

Genomic analysis of multidrug-resistant CTX-M-15-positive Klebsiella pneumoniae belonging to the highly successful ST15 clone isolated from a dog with chronic otitis.

BACKGROUND: Extended-spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae have been increasingly reported worldwide as a frequent cause of human and animal infections. K. pneumoniae belonging to the K24 capsular serotype and sequence type (ST) ST15 has been considered a global successful clone responsible for the spread of the blaCTX-M-15 gene. OBJECTIVE: To report the draft genome sequence of a multidrug-resistant CTX-M-15-positive K. pneumoniae K24-ST15 strain (L3KP1), which was isolated from a dog with chronic otitis. METHODS: Genomic DNA was extracted and sequenced using Illumina NextSeq platform. De novo assembly was performed by SPAdes and in silico prediction accomplished by curated bioinformatics tools. RESULTS: The genome size was calculated at 5 642 348 bp, with a GC content of 57.11%, and comprising 5601 total genes, 52 tRNAs, 8 rRNAs, 9 ncRNAs and 105 pseudogenes. The K. pneumoniae L3KP1 strain belonged to ST15 and carried the yersiniabactin biosynthetic gene cluster [ybt 10 (YbST28) in the integrative conjugative element ICEKp4], and the KL24 locus encoding capsular serotype K24. Besides the blaCTX-M-15 ESBL gene, other clinically important resistance genes to ß-lactams, aminoglycosides, fosfomycin, macrolides, phenicol, quinolones, sulfonamides, tetracyclines and trimethoprim were detected. Additionally, heavy metals and disinfectant resistance genes were also identified. CONCLUSION: This draft genome might be useful for comparative genomic analyses of the international clone of K. pneumoniae K24-ST15-CTX-M-15. In addition, information presented in this study also shed light on the urgent need to monitor ESBL-producing K. pneumoniae in veterinary hospitals.

Comparative analysis of multidrug resistance plasmids and genetic background of CTX-M-producing Escherichia coli recovered from captive wild animals.

Multiple interlinked factors are associated with the global resistome, whereas multidrug-resistant (MDR) pathogens have been related to increased mortality rates in humans and animals. CTX-M-type is the most prevalent extended-spectrum ß-lactamase (ESBL) among Enterobacteriaceae, which raises concern worldwide. Zoological gardens have a high density of animals that live very close to each other and to humans. Therefore, this study aimed to investigate through the whole-genome sequencing (WGS) MDR Escherichia coli lineages obtained from captivity wild animals in a zoo. Genetic background showed a wide resistome for antimicrobials (e.g., blaCTX-M-65, blaCTX-M-8, blaCMY-2, qnrB19), metals (e.g., pcoABCDERS, silABCEP, merACDEPRT), and antibacterial biocides (e.g., sugE, mdfA) among MDR CTX-M-producing E. coli belonging to CC155 and CC156. Mobilome analysis revealed several plasmids, and eight of them were completely characterized, which showed different backbone-encoding genes. Comparative analysis of plasmids blaCTX-M-65/IncHI2-ST3, blaCTX-M-8/IncI1-ST113, and IncQ1 showed a high identity among plasmids obtained from humans and animals worldwide distributed. Besides, several virulence genes, CRISPR, and prophage-related sequences were also detected. The occurrence of MDR E. coli belonging to CCs closely related to humans and food-producing animals and the high similarity among the plasmids from MDR E. coli carrying clinically significant antimicrobial resistance genes may indicate intercontinental dissemination of these lineages and plasmids. Therefore, these findings contribute to the monitoring of antimicrobial resistance and the human-animal-environment interface worldwide. Key Points • Wide resistome for antimicrobials, metals, and antibacterial biocides. • Multidrug resistance plasmids (blaCTX-M-65/IncHI2-ST3, blaCTX-M-8/IncI1-ST113). • Co-occurrence of plasmid-mediated resistance and virulence genes.