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BMC Veterinary Research May 2024Antimicrobial resistance is considered one of the most critical threat for both human and animal health. Recently, reports of infection or colonization by...
Antimicrobial resistance is considered one of the most critical threat for both human and animal health. Recently, reports of infection or colonization by carbapenemase-producing Enterobacterales in companion animals had been described. This study report the first molecular characterization of NDM-producing Enterobacterales causing infections in companion animals from Argentina. Nineteen out of 3662 Enterobacterales isolates analyzed between October 2021 and July 2022 were resistant to carbapenemes by VITEK2C and disk diffusion method, and suspected to be carbapenemase-producers. Ten isolates were recovered from canine and nine from feline animals. Isolates were identified as K. pneumoniae (n = 9), E. coli (n = 6) and E. cloacae complex (n = 4), and all of them presented positive synergy among EDTA and carbapenems disks, mCIM/eCIM indicative of metallo-carbapenemase production and were also positive by PCR for bla gene. NDM variants were determined by Sanger sequencing method. All 19 isolates were resistant to β-lactams and aminoglycosides but remained susceptible to colistin (100%), tigecycline (95%), fosfomycin (84%), nitrofurantoin (63%), minocycline (58%), chloramphenicol (42%), doxycycline (21%), enrofloxacin (5%), ciprofloxacin (5%) and trimethoprim/sulfamethoxazole (5%). Almost all isolates (17/19) co-harbored bla plus bla, one harbored bla alone and the remaining bla. E. coli and E. cloacae complex isolates harbored bla or bla groups, while all K. pneumoniae harbored only bla genes. All E. coli and E. cloacae complex isolates harbored bla, while in K. pneumoniae bla (n = 6), bla (n = 2), and bla plus bla (n = 1) were confirmed. MLST analysis revealed the following sequence types by species, K. pneumoniae: ST15 (n = 5), ST273 (n = 2), ST11, and ST29; E. coli: ST162 (n = 3), ST457, ST224, and ST1196; E. cloacae complex: ST171, ST286, ST544 and ST61. To the best of our knowledge, this is the first description of NDM-producing E. cloacae complex isolates recovered from cats. Even though different species and clones were observed, it is remarkable the finding of some major clones among K. pneumoniae and E. coli, as well as the circulation of NDM as the main carbapenemase. Surveillance in companion pets is needed to detect the spread of carbapenem-resistant Enterobacterales and to alert about the dissemination of these pathogens among pets and humans.
Topics: Animals; Cats; Dogs; Cat Diseases; beta-Lactamases; Argentina; Enterobacteriaceae Infections; Anti-Bacterial Agents; Dog Diseases; Microbial Sensitivity Tests; Pets; Enterobacteriaceae; Escherichia coli; Klebsiella pneumoniae
PubMed: 38702700
DOI: 10.1186/s12917-024-04020-z -
RamA, a transcriptional regulator conferring florfenicol resistance in Leclercia adecarboxylata R25.Folia Microbiologica Dec 2020Due to the inappropriate use of florfenicol in agricultural practice, florfenicol resistance has become increasingly serious. In this work, we studied the novel...
Due to the inappropriate use of florfenicol in agricultural practice, florfenicol resistance has become increasingly serious. In this work, we studied the novel florfenicol resistance mechanism of an animal-derived Leclercia adecarboxylata strain R25 with high-level florfenicol resistance. A random genomic DNA library was constructed to screen the novel florfenicol resistance gene. Gene cloning, gene knockout, and complementation combined with the minimum inhibitory concentration (MIC) detection were conducted to determine the function of the resistance-related gene. Sequencing and bioinformatics methods were applied to analyze the structure of the resistance gene-related sequences. Finally, we obtained a regulatory gene of an RND (resistance-nodulation-cell division) system, ramA, that confers resistance to florfenicol and other antibiotics. The ramA-deleted variant (LA-R25ΔramA) decreased the level of resistance against florfenicol and several other antibiotics, while a ramA-complemented strain (pUCP24-prom-ramA/LA-R25ΔramA) restored the drug resistance. The whole-genome sequencing revealed that there were five RND efflux pump genes (mdtABC, acrAB, acrD, acrEF, and acrAB-like) encoded over the chromosome, and ramA located upstream of the acrAB-like genes. The results of this work suggest that ramA confers resistance to florfenicol and other structurally unrelated antibiotics, presumably by regulating the RND efflux pump genes in L. adecarboxylata R25.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Cloning, Molecular; Computational Biology; Drug Resistance, Multiple, Bacterial; Enterobacteriaceae; Escherichia coli; Gene Knockout Techniques; Microbial Sensitivity Tests; RNA, Ribosomal, 16S; Thiamphenicol; Trans-Activators; Whole Genome Sequencing
PubMed: 32857336
DOI: 10.1007/s12223-020-00816-2 -
MBio Feb 2018The hospital environment is a potential reservoir of bacteria with plasmids conferring carbapenem resistance. Our Hospital Epidemiology Service routinely performs...
The hospital environment is a potential reservoir of bacteria with plasmids conferring carbapenem resistance. Our Hospital Epidemiology Service routinely performs extensive sampling of high-touch surfaces, sinks, and other locations in the hospital. Over a 2-year period, additional sampling was conducted at a broader range of locations, including housekeeping closets, wastewater from hospital internal pipes, and external manholes. We compared these data with previously collected information from 5 years of patient clinical and surveillance isolates. Whole-genome sequencing and analysis of 108 isolates provided comprehensive characterization of /-positive isolates, enabling an in-depth genetic comparison. Strikingly, despite a very low prevalence of patient infections with -positive organisms, all samples from the intensive care unit pipe wastewater and external manholes contained carbapenemase-producing organisms (CPOs), suggesting a vast, resilient reservoir. We observed a diverse set of species and plasmids, and we noted species and susceptibility profile differences between environmental and patient populations of CPOs. However, there were plasmid backbones common to both populations, highlighting a potential environmental reservoir of mobile elements that may contribute to the spread of resistance genes. Clear associations between patient and environmental isolates were uncommon based on sequence analysis and epidemiology, suggesting reasonable infection control compliance at our institution. Nonetheless, a probable nosocomial transmission of sp. from the housekeeping environment to a patient was detected by this extensive surveillance. These data and analyses further our understanding of CPOs in the hospital environment and are broadly relevant to the design of infection control strategies in many infrastructure settings. Carbapenemase-producing organisms (CPOs) are a global concern because of the morbidity and mortality associated with these resistant Gram-negative bacteria. Horizontal plasmid transfer spreads the resistance mechanism to new bacteria, and understanding the plasmid ecology of the hospital environment can assist in the design of control strategies to prevent nosocomial infections. A 5-year genomic and epidemiological survey was undertaken to study the CPOs in the patient-accessible environment, as well as in the plumbing system removed from the patient. This comprehensive survey revealed a vast, unappreciated reservoir of CPOs in wastewater, which was in contrast to the low positivity rate in both the patient population and the patient-accessible environment. While there were few patient-environmental isolate associations, there were plasmid backbones common to both populations. These results are relevant to all hospitals for which CPO colonization may not yet be defined through extensive surveillance.
Topics: Bacterial Proteins; Carbapenem-Resistant Enterobacteriaceae; Hospitals; Humans; Metagenomics; Plasmids; Prevalence; Sanitary Engineering; Water Microbiology; Whole Genome Sequencing; beta-Lactamases
PubMed: 29437920
DOI: 10.1128/mBio.02011-17 -
Journal of Clinical Microbiology Dec 2016Molecular typing has become indispensable in the detection of nosocomial transmission of bacterial pathogens and the identification of sources and routes of transmission...
Molecular typing has become indispensable in the detection of nosocomial transmission of bacterial pathogens and the identification of sources and routes of transmission in outbreak settings, but current methods are labor-intensive, are difficult to standardize, or have limited resolution. Whole-genome multilocus sequence typing (wgMLST) has emerged as a whole-genome sequencing (WGS)-based gene-by-gene typing method that may overcome these limitations and has been applied successfully for several species in outbreak settings. In this study, genus-, genetic-complex-, and species-specific wgMLST schemes were developed for Citrobacter spp., the Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca, and Klebsiella pneumoniae and used to type a national collection of 1,798 extended-spectrum-beta-lactamase-producing Enterobacteriaceae (ESBL-E) isolates obtained from patients in Dutch hospitals. Genus-, genetic-complex-, and species-specific thresholds for genetic distance that accurately distinguish between epidemiologically related and unrelated isolates were defined for Citrobacter spp., the E. cloacae complex, E. coli, and K. pneumoniae wgMLST was shown to have higher discriminatory power and typeability than in silico MLST. In conclusion, the wgMLST schemes developed in this study facilitate high-resolution WGS-based typing of the most prevalent ESBL-producing species in clinical practice and may contribute to further elucidation of the complex epidemiology of antimicrobial-resistant Enterobacteriaceae wgMLST opens up possibilities for the creation of a Web-accessible database for the global surveillance of ESBL-producing bacterial clones.
Topics: Citrobacter; DNA, Bacterial; Enterobacter cloacae; Enterobacteriaceae; Enterobacteriaceae Infections; Escherichia coli; Humans; Klebsiella oxytoca; Klebsiella pneumoniae; Multilocus Sequence Typing; beta-Lactamases
PubMed: 27629900
DOI: 10.1128/JCM.01648-16 -
Journal of Comparative Pathology Jan 2005Enteric bacteria with a demonstrable or potential ability to form attaching-effacing lesions, so-called attaching-effacing (AE) bacteria, have been found in the... (Review)
Review
Enteric bacteria with a demonstrable or potential ability to form attaching-effacing lesions, so-called attaching-effacing (AE) bacteria, have been found in the intestinal tracts of a wide variety of warm-blooded animal species, including man. In some host species, for example cattle, pigs, rabbits and human beings, attaching-effacing Escherichia coli (AEEC) have an established role as enteropathogens. In other host species, AE bacteria are of less certain significance. With continuing advances in the detection and typing of AE strains, the importance of these bacteria for many hosts is likely to become clearer. The pathogenic effects of AE bacteria result from adhesion to the intestinal mucosa by a variety of mechanisms, culminating in the formation of the characteristic intimate adhesion of the AE lesion. The ability to induce AE lesions is mediated by the co-ordinated expression of some 40 bacterial genes organized within a so-called pathogenicity island, known as the "Locus for Enterocyte Effacement". It is also believed that the production of bacterial toxins, principally Vero toxins, is a significant virulence factor for some AEEC strains. Recent areas of research into AE bacteria include: the use of Citrobacter rodentium to model human AEEC disease; quorum-sensing mechanisms used by AEEC to modulate virulence gene expression; and the potential role of adhesion in the persistent colonization of the intestine by AE bacteria. This review of AE bacteria covers their molecular biology, their occurrence in various animal species, and the diagnosis, pathology and clinical aspects of animal diseases with which they are associated. Reference is made to human pathogens where appropriate. The focus is mainly on natural colonization and disease, but complementary experimental data are also included.
Topics: Animals; Bacterial Adhesion; Enterobacteriaceae; Enterobacteriaceae Infections; Escherichia coli; Humans
PubMed: 15629476
DOI: 10.1016/j.jcpa.2004.09.005 -
Microbiology Spectrum Oct 2021We isolated eight tigecycline-resistant strains from a pig farm in Shanghai, China, including Escherichia coli ( = 1), Proteus cibarius ( = 1), and Enterobacter...
We isolated eight tigecycline-resistant strains from a pig farm in Shanghai, China, including Escherichia coli ( = 1), Proteus cibarius ( = 1), and Enterobacter hormaechei ( = 6). Two of them (E. coli and P. cibarius) were positive for (X). E. coli SH19PTE6 contained an IncFIA18/IncFIB(K)/IncX1 hybrid plasmid pYUSHP6-tetX, highly similar to other (X)-bearing hybrid plasmids from E. coli in China. In P. cibarius SH19PTE4, (X) was located within a new chromosomal integrative and conjugative element (ICE), ICEChn2, belonging to the SXT/R391 ICE family. All tigecycline-resistant E. hormaechei isolates carried the (A) variant; cloning and transfer of this (A) variant into various hosts increased their MICs for tigecycline (4- to 8-fold). Tigecycline resistance observed on a pig farm is mediated by the (A) variant and (X) via a plasmid or ICE. The rational use of antibiotics such as doxycycline and surveillance of tigecycline resistance in livestock are warranted. As a last-resort antimicrobial agent to treat serious infections, the emergence and spread of tigecycline resistance in and Acinetobacter have raised global concerns. Multiple mechanisms mediate tigecycline resistance in , such as the monooxygenase Tet(X), mutations in Tet proteins, and overexpression of efflux pumps. Although tigecycline is not approved for animals, tigecycline resistance has been observed in Escherichia coli, Proteus cibarius, and Enterobacter hormaechei isolates on a pig farm, mediated by the (A) variant and (X) via a plasmid or ICE. The heavy use of tetracyclines such as doxycycline in food-producing animals in China may be the reason for the emergence and transmission of tigecycline resistance.
Topics: Animals; Anti-Bacterial Agents; Carrier State; China; Drug Resistance, Bacterial; Enterobacteriaceae; Farms; Microbial Sensitivity Tests; Plasmids; Swine; Tigecycline
PubMed: 34523976
DOI: 10.1128/Spectrum.00416-21 -
The ISME Journal Mar 2020While genome erosion is extensively studied in intracellular symbionts, the metabolic implications of reductive evolution in microbes subsisting extracellularly remain...
While genome erosion is extensively studied in intracellular symbionts, the metabolic implications of reductive evolution in microbes subsisting extracellularly remain poorly understood. Stammera capleta-an extracellular symbiont in leaf beetles-possesses an extremely reduced genome (0.27 Mb), enabling the study of drastic reductive evolution in the absence of intracellularity. Here, we outline the genomic and transcriptomic profiles of Stammera and its host to elucidate host-symbiont metabolic interactions. Given the symbiont's substantial demands for nutrients and membrane components, the host's symbiotic organ shows repurposing of internal resources by upregulating nutrient transporters and cuticle-processing genes targeting epithelial chitin. Facilitated by this supplementation and its localization, Stammera exhibits a highly streamlined gene expression profile and a fermentation pathway for energy conversion, sharply contrasting the respiratory metabolism retained by most intracellular symbionts. Our results provide insights into a tightly regulated and metabolically integrated extracellular symbiosis, expanding our understanding of the minimal metabolism required to sustain life outside of a host cell.
Topics: Animals; Coleoptera; Enterobacteriaceae; Fermentation; Genomics; Symbiosis
PubMed: 31796934
DOI: 10.1038/s41396-019-0562-1 -
Yonsei Medical Journal Dec 1998Extended-spectrum beta-lactamases (ESBLs) in gram-negative organisms have been implicated as the enzymes responsible for resistance to oxyimino-cephalosporins. The... (Review)
Review
Extended-spectrum beta-lactamases (ESBLs) in gram-negative organisms have been implicated as the enzymes responsible for resistance to oxyimino-cephalosporins. The incidence of ESBL-producers in Korean isolates of Escherichia coli and Klebsiella pneumoniae were in the range of 4.8-7.5% and 22.5-22.8%, respectively. The ESBL-producing isolates revealed variable levels of resistance to cefotaxime, ceftazidime and aztreonam. They also showed the elevated MIC values of non-beta-lactam antibiotics. SHV-12 and SHV-2a were the enzymes most frequently found in K. pneumoniae strains, but TEM-52 was the most prevalent in E. coli isolates. About 15% of ESBL-producing isolates of Enterobacteriaceae produced CMY-1 enzyme, which conferred resistance to cephamycins such as cefoxitin as well as oxyimino-cephalosporins. Thus, the most common types of ESBLs in Korea are TEM-52, SHV-12 SHV-2a, and CMY-1.
Topics: Drug Resistance, Microbial; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Korea; beta-Lactamases
PubMed: 10097677
DOI: 10.3349/ymj.1998.39.6.514 -
Emerging Microbes & Infections 2020Mobile colistin resistance () genes represent an emerging challenge. Here we describe a novel gene, , on an IncFIA plasmid of an clinical strain. has the highest...
Mobile colistin resistance () genes represent an emerging challenge. Here we describe a novel gene, , on an IncFIA plasmid of an clinical strain. has the highest nucleotide identity (79.69%) with and encodes MCR-10 with 82.93% amino acids identical to MCR-9. confers 4-fold increase in colistin MIC (from 1 to 4 mg/L) when cloned into a colistin-susceptible strain. By screening GenBank, was found in various species of countries in four continents, suggesting that this gene has widely spread. MCR-10 shows 79.04% to 83.67% amino acid identity and highly conserved predicted protein structures with chromosomally encoded MCR-like phosphoethanolamine transferases (designated MCR-B here) of various species. MCR-10, MCR-9 and MCR-B proteins may, therefore, originate from a common ancestor. was adjacent to a site-specific recombinase-encoding gene and was bracketed by IS and may be mobilized by site-specific recombination or composite transposon. Our results indicate that is a novel plasmid-borne colistin resistance gene and warrants immediate monitoring and further studies.
Topics: Amino Acid Sequence; Bacterial Proteins; Colistin; Databases, Genetic; Drug Resistance, Bacterial; Enterobacteriaceae; Models, Molecular; Plasmids; Protein Structure, Tertiary; Sequence Analysis, Protein
PubMed: 32116151
DOI: 10.1080/22221751.2020.1732231 -
Emerging Infectious Diseases Jun 2016For identification of polymyxin resistance in Enterobacteriaceae, we developed a rapid test that detects glucose metabolization associated with bacterial growth in the...
For identification of polymyxin resistance in Enterobacteriaceae, we developed a rapid test that detects glucose metabolization associated with bacterial growth in the presence of a defined concentration of colistin or polymyxin B. Formation of acid metabolites is evidenced by a color change (orange to yellow) of a pH indicator (red phenol). To evaluate the test, we used bacterial colonies of 135 isolates expressing various mechanisms of colistin resistance (intrinsic, chromosomally encoded, and plasmid-mediated MCR-1) and 65 colistin-susceptible isolates. Sensitivity and specificity were 99.3% and 95.4%, respectively, compared with the standard broth microdilution method. This new test is inexpensive, easy to perform, sensitive, specific, and can be completed in <2 hours. It could be useful in countries facing endemic spread of carbapenemase producers and for which polymyxins are last-resort drugs.
Topics: Anti-Bacterial Agents; Drug Resistance, Bacterial; Enterobacteriaceae; Enterobacteriaceae Infections; Genes, Bacterial; Genotype; Humans; Microbial Sensitivity Tests; Polymyxins
PubMed: 27191712
DOI: 10.3201/eid2206.151840