scholarly journals Escaping the Fate of Sisyphus: Assessing Resistome Hybridization Baits for Antimicrobial Resistance Gene Capture

2021 ◽  
Author(s):  
Megan S. Beaudry ◽  
Jesse C. Thomas ◽  
Rodrigo Baptista ◽  
Amanda Sullivan ◽  
William Norfolk ◽  
...  

Finding, characterizing, and monitoring reservoirs for antimicrobial resistance (AMR) is vital to protecting public health. Hybridization capture baits are an accurate, sensitive, and cost-effective technique used to enrich and characterize DNA sequences of interest, including antimicrobial resistance genes (ARGs), in complex environmental samples. We demonstrate the continued utility of a set of 19,933 hybridization capture baits designed from the Comprehensive Antibiotic Resistance Database (CARD)v1.1.2 and Pathogenicity Island Database (PAIDB)v2.0, targeting 3,565 unique nucleotide sequences that confer resistance. We demonstrate the efficiency of our bait set on a custom-made resistance mock community and complex environmental samples to increase the proportion of on-target reads as much as >200-fold. However, keeping pace with newly discovered ARGs poses a challenge when studying AMR, because novel ARGs are continually being identified and would not be included in bait sets designed prior to discovery. We provide imperative information on how our bait set performs against CARDv3.3.1, as well as a generalizable approach for deciding when and how to update hybridization capture bait sets. This research encapsulates the full life cycle of baits for hybridization capture of the resistome from design and validation (both in silico and in vitro) to utilization and forecasting updates and retirement.

2008 ◽  
Vol 74 (19) ◽  
pp. 6085-6090 ◽  
Author(s):  
Paul R. Hunter ◽  
Dawn C. Wilkinson ◽  
Louise A. Catling ◽  
Gary C. Barker

ABSTRACT This paper presents the results of a meta-analysis of published transfer rates of antimicrobial resistance genes. A total of 34 papers were identified, of which 28 contained rates estimated in relation to either donor or recipient bacterial counts. The published rates ranged from 10−2 to 10−9. Generalized linear modeling was conducted to identify the factors influencing this variation. Highly significant associations between transfer frequency and both the donor (P = 1.2 � 10−4) and recipient (P = 1.0 � 10−5) genera were found. Also significant was whether the donor and recipient strains were of the same genus (P = 0.023) and the nature of the genetic element (P = 0.0019). The type of experiment, in vivo or in vitro, approached statistical significance (P = 0.12). Parameter estimates from a general linear model were used to estimate the probability of transfer of antimicrobial resistance genes to potential pathogens in the intestine following oral ingestion. The mean logarithms of these probabilities are in the range of [−7.0, −3.1]. These probability distributions are suitable for use in the quantitative assessment of the risk of transfer of antimicrobial resistance genes to the intestinal flora of humans and animals.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Adrienn Gréta Tóth ◽  
István Csabai ◽  
Gergely Maróti ◽  
Ákos Jerzsele ◽  
Attila Dubecz ◽  
...  

AbstractAntimicrobial resistance (AMR) is a global threat gaining more and more practical significance every year. The main determinants of AMR are the antimicrobial resistance genes (ARGs). Since bacteria can share genetic components via horizontal gene transfer, even non-pathogenic bacteria may provide ARG to any pathogens which they become physically close to (e.g. in the human gut). In addition, fermented food naturally contains bacteria in high amounts. In this study, we examined the diversity of ARG content in various kefir and yoghurt samples (products, grains, bacterial strains) using a unified metagenomic approach. We found numerous ARGs of commonly used fermenting bacteria. Even with the strictest filter restrictions, we identified ARGs undermining the efficacy of aminocoumarins, aminoglycosides, carbapenems, cephalosporins, cephamycins, diaminopyrimidines, elfamycins, fluoroquinolones, fosfomycins, glycylcyclines, lincosamides, macrolides, monobactams, nitrofurans, nitroimidazoles, penams, penems, peptides, phenicols, rifamycins, tetracyclines and triclosan. In the case of gene lmrD, we detected genetic environment providing mobility of this ARG. Our findings support the theory that during the fermentation process, the ARG content of foods can grow due to bacterial multiplication. The results presented suggest that the starting culture strains of fermented foods should be monitored and selected in order to decrease the intake of ARGs via foods.


2020 ◽  
Vol 726 ◽  
pp. 138100
Author(s):  
João Pedro Rueda Furlan ◽  
Lucas David Rodrigues dos Santos ◽  
Jéssica Aparecida Silva Moretto ◽  
Micaela Santana Ramos ◽  
Inara Fernanda Lage Gallo ◽  
...  

2014 ◽  
Vol 80 (12) ◽  
pp. 3656-3666 ◽  
Author(s):  
Basanta Kumar Biswal ◽  
Ramzi Khairallah ◽  
Kareem Bibi ◽  
Alberto Mazza ◽  
Ronald Gehr ◽  
...  

ABSTRACTWastewater discharges may increase the populations of pathogens, includingEscherichia coli, and of antimicrobial-resistant strains in receiving waters. This study investigated the impact of UV and peracetic acid (PAA) disinfection on the prevalence of virulence and antimicrobial resistance genes in uropathogenicEscherichia coli(UPEC), the most abundantE. colipathotype in municipal wastewaters. Laboratory disinfection experiments were conducted on wastewater treated by physicochemical, activated sludge, or biofiltration processes; 1,766E. coliisolates were obtained for the evaluation. The target disinfection level was 200 CFU/100 ml, resulting in UV and PAA doses of 7 to 30 mJ/cm2and 0.9 to 2.0 mg/liter, respectively. The proportions of UPECs were reduced in all samples after disinfection, with an average reduction by UV of 55% (range, 22% to 80%) and by PAA of 52% (range, 11% to 100%). Analysis of urovirulence genes revealed that the decline in the UPEC populations was not associated with any particular virulence factor. A positive association was found between the occurrence of urovirulence and antimicrobial resistance genes (ARGs). However, the changes in the prevalence of ARGs in potential UPECs were different following disinfection, i.e., UV appears to have had no effect, while PAA significantly reduced the ARG levels. Thus, this study showed that both UV and PAA disinfections reduced the proportion of UPECs and that PAA disinfection also reduced the proportion of antimicrobial resistance gene-carrying UPEC pathotypes in municipal wastewaters.


2020 ◽  
Author(s):  
Robert Pieper ◽  
Temesgen Dadi ◽  
Lukasz Grzeskowiak ◽  
Laura Pieper ◽  
Britta Siegmund ◽  
...  

Abstract Background: Clostridium difficile infection (CDI) is an increasing zoonotic health threat and has also been documented as a cause of enteritis outbreaks in neonatal pigs. Furthermore, CDI in neonatal piglets cause changes in microbial gut colonization. We hypothesized that an imbalanced microbial colonization in piglets with CDI could be associated with an altered abundance of antimicrobial resistance genes. Results: We analyzed fecal metagenomic data of lactating sows (S), their piglets during suckling (SP), the same piglets two weeks after weaning (WP), 5-day old artificially reared and formula-fed siblings (FP) and FP infected with C. difficile (FP-CD) for microbiota composition and antimicrobial resistance gene abundance. FP and FP-CD piglets had an immature-type microbiota and increased abundance of antimicrobial resistance genes. A co-occurrence of genes encoding for resistance against aminoglycosides (e.g. aph(3”)-lb, aph(6)-ld, ant(2”)-la), β-lactams (blaCTX-M, blaTEM), fluoroquinolones (pat(A) macrolides (mph(A)), sulfonamides (sul1, sul2), polypeptides (e.g. pmrB, pmrC, arnA, bac(A)) and tetracyclines (e.g. tet(A-D),) was observed. Conclusion: Increased abundance of antimicrobial resistance genes in formula feeding and concomitant CDI may be associated with therapeutic resistance later in life and warrant further studies.


2006 ◽  
Vol 72 (1) ◽  
pp. 443-448 ◽  
Author(s):  
Artashes R. Khachatryan ◽  
Dale D. Hancock ◽  
Thomas E. Besser ◽  
Douglas R. Call

ABSTRACT Maintenance of antimicrobial drug resistance in bacteria can be influenced by factors unrelated to direct selection pressure such as close linkage to other selectively advantageous genes and secondary advantage conveyed by antimicrobial resistance genes in the absence of drug selection. Our previous trials at a dairy showed that the maintenance of the antimicrobial resistance genes is not influenced by specific antimicrobial selection and that the most prevalent antimicrobial resistance phenotype of Escherichia coli is specifically selected for in young calves. In this paper we examine the role of secondary advantages conveyed by antimicrobial resistance genes. We tested antimicrobial-susceptible null mutant strains for their ability to compete with their progenitor strains in vitro and in vivo. The null mutant strains were generated by selection for spontaneous loss of resistance genes in broth supplemented with fusaric acid or nickel chloride. On average, the null mutant strains were as competitive as the progenitor strains in vitro and in newborn calves (in vivo). Inoculation of newborn calves at the dairy with antimicrobial-susceptible strains of E. coli did not impact the prevalence of antimicrobial-resistant E. coli. Our results demonstrate that the antimicrobial resistance genes are not responsible for the greater fitness advantage of antimicrobial-resistant E. coli in calves, but the farm environment and the diet clearly exert critical selective pressures responsible for the maintenance of antimicrobial resistance genes. Our current hypothesis is that the antimicrobial resistance genes are linked to other genes responsible for differential fitness in dairy calves.


2019 ◽  
Author(s):  
Aislinn D. Rowan-Nash ◽  
Rafael Araos ◽  
Erika M.C. D’Agata ◽  
Peter Belenky

ABSTRACTBackgroundThe issue of antimicrobial resistance continues to grow worldwide, and long-term care facilities are significant reservoirs of antimicrobial-resistant organisms, in part due to high frequency of antimicrobial use. Patients with advanced dementia are particularly vulnerable to multidrug-resistant organism acquisition and antimicrobial overuse, which has negative consequences for the gut microbiome and can contribute to the selection and propagation of antimicrobial resistance genes. In this study, we longitudinally examined a group of advanced dementia patients treated with the fluoroquinolone antimicrobial levofloxacin, finding a correlation between abundance of pathogens and antimicrobial resistance genes, which we confirmed in a larger cohort of subjects with advanced dementia.ResultsWe observed significant inter- and intra-subject heterogeneity in the composition of the microbiota of the longitudinal levofloxacin cohort, suggesting temporal instability. Within this dataset, we did not find significant impacts of levofloxacin on the diversity, composition, function, or resistome of the gut microbiota of this population. However, we were able to link the antimicrobial resistance gene burden in a sample with the relative abundance of several pathobionts – particularly Escherichia coli, Proteus mirabilis, and Enterococcus faecalis, as well as less-prevalent species including Providencia stuartii and Staphylococcus haemolyticus. Furthermore, we used metagenomic assembly and binning to demonstrate that these species had higher genomic resistance gene levels than common gut commensals, and we were able to predict antimicrobial resistance gene burden from the relative abundances of these species in a separate, larger cohort from the same population.ConclusionsWe found that the relative abundances of several pathobionts were correlated with and were even predictive of the level of antimicrobial resistance genes in corresponding samples, and that these species carried high levels of resistances genes in their assembled genomes. In order to test this observation, we utilized a larger metagenomics dataset from a similar population and confirmed the association between pathobiont abundance and antimicrobial resistance genes. Given the high frequency with which these species were found at high levels in this population and the underlying vulnerability to infection with multidrug resistant organisms of advanced dementia patients, attention to microbial blooms of these species may be warranted. Additionally, in this study, we were able to utilize genomic assembly from metagenomic data to more definitively associate antimicrobial resistance gene levels with specific assembled species; as this technology continues to develop, assembly could prove to be a valuable method to monitor both specific resistance genes and blooms of multidrug-resistant organisms.


Author(s):  
Chaitra Shankar ◽  
Soumya Basu ◽  
Binesh Lal ◽  
Sathiya Shanmugam ◽  
Karthick Vasudevan ◽  
...  

BackgroundThe incidence of hypervirulent (hv) carbapenem-resistant (CR) Klebsiella pneumoniae (Kp) is increasing globally among various clones and is also responsible for nosocomial infections. The CR-hvKp is formed by the uptake of a virulence plasmid by endemic high-risk clones or by the uptake of plasmids carrying antimicrobial resistance genes by the virulent clones. Here, we describe CR-hvKp from India belonging to high-risk clones that have acquired a virulence plasmid and are phenotypically unidentified due to lack of hypermucoviscosity.MethodsTwenty-seven CRKp isolates were identified to possess rmpA2 by whole-genome sequencing; and resistance and virulence determinants were characterized. By in silico protein modeling (and validation), protein backbone stability analysis, and coarse dynamics study, the fitness of RmpA, RmpA2, and aerobactin-associated proteins-IucA and IutA, were determined to establish a reliable marker for clinical identification of CR-hvKp.ResultsThe CR-hvKp belonged to multidrug-resistant (MDR) high-risk clones such as CG11, CG43, ST15, and ST231 and carried OXA-232 as the predominant carbapenemase followed by NDM. The virulence plasmid belonged to IncHI1B replicon type and carried frameshifted and truncated rmpA and rmpA2. This resulted in a lack of hypermucoviscous phenotype. However, functional aerobactin was expressed in all high-risk clones. In silico analysis portrayed that IucA and IutA were more stable than classical RmpA. Furthermore, IucA and IutA had lower conformational fluctuations in the functional domains than the non-functional RmpA2, which increases the fitness cost of the latter for its maintenance and expression among CR-hvKp. Hence, RmpA and RmpA2 are likely to be lost among CR-hvKp owing to the increased fitness cost while coding for essential antimicrobial resistance and virulence factors.ConclusionIncreasing incidence of convergence of AMR and virulence is observed among K. pneumoniae globally, which warrants the need for reliable markers for identifying CR-hvKp. The presence of non-functional RmpA2 among high-risk clones highlights the significance of molecular identification of CR-hvKp. The negative string test due to non-functional RmpA2 among CR-hvKp isolates challenges phenotypic screening and faster identification of this pathotype. This can potentially be counteracted by projecting aerobactin as a stable, constitutively expressed, and functional marker for rapidly evolving CR-hvKp.


FACETS ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 128-138 ◽  
Author(s):  
Claire N. Freeman ◽  
Lena Scriver ◽  
Kara D. Neudorf ◽  
Lisbeth Truelstrup Hansen ◽  
Rob C. Jamieson ◽  
...  

Wastewater treatment plants (WWTPs) have been identified as hotspots for antimicrobial resistance genes (ARGs) and thus represent a critical point where patterns in ARG abundances can be monitored prior to their release into the environment. The aim of the current study was to measure the impact of the release of the final treated effluent (FE) on the abundance of ARGs in the receiving water of a recently upgraded WWTP in the Canadian prairies. Sample nutrient content (phosphorous and nitrogen species) was measured as a proxy for WWTP functional performance, and quantitative PCR (qPCR) was used to measure the abundance of eight ARGs, the intI1 gene associated with class I integrons, and the 16S rRNA gene. The genes ermB, sul1, intI1, blaCTX-M, qnrS, and tetO all had higher abundances downstream of the WWTP, consistent with the genes with highest abundance in the FE. These findings are consistent with the increasing evidence suggesting that human activity affects the abundances of ARGs in the environment. Although the degree of risk associated with releasing ARGs into the environment is still unclear, understanding the environmental dimension of this threat will help develop informed management policies to reduce the spread of antibiotic resistance and protect public health.


2019 ◽  
Vol 63 (4) ◽  
Author(s):  
Wenming Zhu ◽  
Adrian Lawsin ◽  
Rebecca L. Lindsey ◽  
Dhwani Batra ◽  
Kristen Knipe ◽  
...  

ABSTRACT Four Enterobacteriaceae clinical isolates bearing mcr-1 gene-harboring plasmids were characterized. All isolates demonstrated the ability to transfer colistin resistance to Escherichia coli; plasmids were stable in conjugants after multiple passages on nonselective media. mcr-1 was located on an IncX4 (n = 3) or IncN (n = 1) plasmid. The IncN plasmid harbored 13 additional antimicrobial resistance genes. Results indicate that the mcr-1-bearing plasmids in this study were highly transferable in vitro and stable in the recipients.


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