Using WGS to identify antibiotic resistance genes and predict antimicrobial resistance phenotypes in MDR Acinetobacter baumannii in Tanzania

ABSTRACTWe report first complete genome sequence and analysis of an extreme drug resistance (XDR) nosocomial Stenotrophomonas maltophilia that is resistant to the mainstream drugs i.e. trimethoprim/sulfamethoxazole (TMP/SXT) and levofloxacin. Taxonogenomic analysis revealed it to be a novel genomospecies of the Stenotrophomonas maltophilia complex (Smc). Comprehensive genomic investigation revealed fourteen dynamic regions (DRs) exclusive to SM866, consisting of diverse antibiotic resistance genes, efflux pumps, heavy metal resistance, various transcriptional regulators etc. Further, resistome analysis of Smc clearly depicted SM866 to be an enriched strain, having diversified resistome consisting of sul1 and sul2 genes. Interestingly, SM866 does not have any plasmid but it harbors two diverse super-integrons of chromosomal origin. Apart from genes for sulfonamide resistance (sul1 and sul2), both of these integrons harbor an array of antibiotic resistance genes linked to ISCR (IS91-like elements common regions) elements. These integrons also harbor genes encoding resistance to commonly used disinfectants like quaternary ammonium compounds and heavy metals like mercury. Hence, isolation of a novel strain belonging to a novel sequence type (ST) and genomospecies with diverse array of resistance from a tertiary care unit of India indicates extent and nature of selection pressure driving XDRs in hospital settings. There is an urgent need to employ complete genome based investigation using emerging technologies for tracking emergence of XDR at the global level and designing strategies of sanitization and antibiotic regime.Impact StatementThe hospital settings in India have one of the highest usage of antimicrobials and heavy patient load. Our finding of a novel clinical isolate of S. maltophilia complex with two super-integrons harbouring array of antibiotic resistance genes along with antimicrobials resistance genes indicates the extent and the nature of selection pressures in action. Further, the presence of ISCR type of transposable elements on both integrons not only indicates its propensity to transfer resistome but also their chromosomal origin suggests possibilities for further genomic/phenotypic complexities. Such complex cassettes and strain are potential threat to global health care. Hence, there is an urgent need to employ cost-effective long read technologies to keep vigilance on novel and extreme antimicrobial resistance pathogens in populous countries. There is also need for surveillance for usage of antimicrobials for hygiene and linked/rapid co-evolution of extreme drug resistance in nosocomial pathogens. Our finding of the chromosomal encoding XDR will shed a light on the need of hour to understand the evolution of an opportunistic nosocomial pathogen belonging to S. maltophilia.RepositoriesComplete genome sequence of Stenotrophomonas maltophilia SM866: CP031058

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Acquisition of a genomic resistance island (AbGRI5) from global clone 2 through homologous recombination in a clinical Acinetobacter baumannii isolate

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkaa389 ◽

2020 ◽

Vol 76 (1) ◽

pp. 65-69

Author(s):

Xiaoting Hua ◽

Robert A Moran ◽

Qingye Xu ◽

Jintao He ◽

Youhong Fang ◽

...

Keyword(s):

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Whole Genome Sequence ◽

Oxford Nanopore ◽

History Of ◽

Agar Dilution ◽

Resistance Island ◽

New Location

Abstract Objectives To reconstruct the evolutionary history of the clinical Acinetobacter baumannii XH1056, which lacks the Oxford scheme allele gdhB. Methods Susceptibility testing was performed using broth microdilution and agar dilution. The whole-genome sequence of XH1056 was determined using the Illumina and Oxford Nanopore platforms. MLST was performed using the Pasteur scheme and the Oxford scheme. Antibiotic resistance genes were identified using ABRicate. Results XH1056 was resistant to all antibiotics tested, apart from colistin, tigecycline and eravacycline. MLST using the Pasteur scheme assigned XH1056 to ST256. However, XH1056 could not be typed with the Oxford MLST scheme as gdhB is not present. Comparative analyses revealed that XH1056 contains a 52 933 bp region acquired from a global clone 2 (GC2) isolate, but is otherwise closely related to the ST23 A. baumannii XH858. The acquired region in XH1056 also contains a 34 932 bp resistance island that resembles AbGRI3 and contains the armA, msrE-mphE, sul1, blaPER-1, aadA1, cmlA1, aadA2, blaCARB-2 and ere(B) resistance genes. Comparison of the XH1056 chromosome to that of GC2 isolate XH859 revealed that the island in XH1056 is in the same chromosomal region as that in XH859. As this island is not in the standard AbGRI3 position, it was named AbGRI5. Conclusions XH1056 is a hybrid isolate generated by the acquisition of a chromosomal segment from a GC2 isolate that contains a resistance island in a new location—AbGRI5. As well as generating ST256, it appears likely that a single recombination event is also responsible for the acquisition of AbGRI5 and its associated antibiotic resistance genes.

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An Analysis of the Antibiotic Resistance Genes of Multi-Drug Resistant (MDR)Acinetobacter baumannii

Korean Journal of Clinical Laboratory Science ◽

10.15324/kjcls.2016.48.3.217 ◽

2016 ◽

Vol 48 (3) ◽

pp. 217-224 ◽

Cited By ~ 2

Author(s):

Jina Lim ◽

Gyusang Lee ◽

Yeonim Choi ◽

Jongbae Kim

Keyword(s):

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Drug Resistant

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Case report: Detection of aadB and tet (39) on the plasmid of Acinetobacter baumannii TN81 in Vietnam through next-generation sequencing and bioinformatics analysis

Tạp chí Y học Dự phòng ◽

10.51403/0868-2836/2021/336 ◽

2021 ◽

Vol 31 (4) ◽

pp. 51-60

Author(s):

Vu Nhi Ha ◽

Kieu Chi Thanh ◽

Nguyen Thai Son ◽

Dao Van Thang ◽

Tran Huy Hoang

Keyword(s):

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Resistance Genes ◽

De Novo Assembly ◽

De Novo ◽

Antibiotic Resistance Genes ◽

Common Mechanism ◽

Genes Encoding ◽

Short Read Sequence ◽

Genome Shotgun Sequence

Acinetobacter baumannii (A. baumannii) is currently ranked as the frst concern for the development of new antibiotics due to its capacity of resistance to all available families of antibiotics. The most common mechanism of antibiotic resistance development in A. baumannii is through the acquisition of mobile genetic elements such as plasmid, transposon and integrons carrying resistance genes. A. baumannii strain TN81 was isolated from sputum specimen of a 45-year-old man at Thanh Nhan Hospital (Hanoi, Vietnam) and confrmed to be a multidrug resistance strain with high minimum inhibitory concentration value of 8/9 type of antibiotics, especially colistin. De novo assembly of the whole genome shotgun sequence of strain TN81 yielded an estimated genome size of 3,739,193 bp with 593 contigs and N50 is 9,126 bp. MLST analysis showed that TN81 belongs to ST164, which was frst reported as genome assembly in Vietnam. Resistance genes identifcation through database found that TN81 contained 12 genes encoding for antibiotic resistance. Notably, we performed de novo assembly of plasmid through short read sequence and identifed two potential plasmid-encoded antibiotic resistance genes (ant(2’’)-Ia / aadB and tet (39), which were reported for the first time as in ST164 group. This study aimed to investigate the plasmid-containing antibiotic resistance genes from a nosocomial isolate of Acinetobacter baumannii. Conclusively, all of these results would be crucial information on antibiotic resistance in A. baumannii in Vietnam.

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Effect of frameshift mutagen acriflavine on control of resistance genes in Acinetobacter baumannii

Journal of Medical Microbiology ◽

10.1099/jmm.0.025544-0 ◽

2011 ◽

Vol 60 (2) ◽

pp. 211-215 ◽

Cited By ~ 8

Author(s):

B. S. Lopes ◽

A. Hamouda ◽

J. Findlay ◽

S. G. B. Amyes

Keyword(s):

Gene Expression ◽

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Resistance Genes ◽

Outer Membrane Proteins ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Multidrug Resistant ◽

The Body

Acinetobacter baumannii is a Gram-negative pathogenic bacterium that often exhibits a multidrug-resistant phenotype causing infections at various sites of the body and increasingly leading to septicaemic shock. This study evaluated the role of acriflavine, a frameshift mutagen, on the movement of insertion sequence ISAba1 in clinical isolates of A. baumannii, with the focus on changes in expression levels of the bla ADC and bla OXA-51-like genes. Resistance profiles were assessed with consideration of ISAba1 acting as a promoter upstream of the bla ADC or bla OXA-51-like gene. ISAba1 movement was observed in the acriflavine mutants Ab153M and Ab1225M. Ab153M exhibited an increase in the MIC values of carbapenems and ceftazidime, with ISAba1 gained upstream of the bla ADC and bla OXA-51-like genes, correlating with an increase in gene expression. Reduced expression of the 17, 23 and 25 kDa outer-membrane proteins (OMPs) was also observed in Ab153M. There was a significant decrease in MIC values of carbapenems with the loss of ISAba1 upstream of the bla ADC and bla OXA-51-like genes in strain Ab1225M, and a significant decrease in bla OXA-51-like gene expression and, to a lesser extent, in bla ADC expression. Ab1225M and a serially subcultured Ab1225 strain (Ab1225s) exhibited overexpression of the 17, 23, 25 and 27 kDa OMPs. There was a decrease in MIC values of the carbapenems and piperacillin/tazobactam but not of ceftazidime in Ab1225s, which had ISAba1 upstream of the bla ADC and bla OXA-51-like genes. A significant decrease in bla OXA-51-like expression was observed in Ab1225s, whereas the expression of bla ADC was similar to that in the Ab1225 parental strain. The attenuation in this strain may be due to overexpression of OMPs and it is clear that, even if ISAba1 is present upstream of an antibiotic resistance gene, it may not necessarily contribute towards the overexpression of antibiotic resistance genes (bla OXA-51-like in Ab1225s). Movement of the IS element within the A. baumannii chromosome may be an important regulatory mechanism employed by the bacterium under particular stress conditions, and the ability to upregulate the expression of antibiotic resistance genes is likely to be an important factor in the pathogenicity of this bacterium.

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Screening and Quantification of the Expression of Antibiotic Resistance Genes in Acinetobacter baumannii with a Microarray

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01037-09 ◽

2009 ◽

Vol 54 (1) ◽

pp. 333-340 ◽

Cited By ~ 59

Author(s):

Sébastien Coyne ◽

Ghislaine Guigon ◽

Patrice Courvalin ◽

Bruno Périchon

Keyword(s):

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Resistance Genes ◽

Efflux Pump ◽

Acquired Resistance ◽

Antibiotic Resistance Genes ◽

Efflux Pumps ◽

Single Step ◽

Resistance Determinants

ABSTRACT An oligonucleotide-based DNA microarray was developed to evaluate expression of genes for efflux pumps in Acinetobacter baumannii and to detect acquired antibiotic resistance determinants. The microarray contained probes for 205 genes, including those for 47 efflux systems, 55 resistance determinants, and 35 housekeeping genes. The microarray was validated by comparative analysis of mutants overexpressing or deficient in the pumps relative to the parental strain. The performance of the microarray was also evaluated using in vitro single-step mutants obtained on various antibiotics. Overexpression, confirmed by quantitative reverse transcriptase PCR, of RND efflux pumps AdeABC, due to a G30D substitution in AdeS in a multidrug-resistant (MDR) strain obtained on gentamicin, and AdeIJK, in two mutants obtained on cefotaxime or tetracycline, was detected. A new efflux pump, AdeFGH, was found to be overexpressed in a mutant obtained on chloramphenicol. Study of MDR clinical isolates, including the AYE strain, whose entire sequence has been determined, indicated overexpression of AdeABC and of the chromosomally encoded cephalosporinase as well as the presence of several acquired resistance genes. The overexpressed and acquired determinants detected by the microarray could account for nearly the entire MDR phenotype of the isolates. The microarray is potentially useful for detection of resistance in A. baumannii and should allow detection of new efflux systems associated with antibiotic resistance.

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Novel Aminoglycoside Resistance Transposons and Transposon-Derived Circular Forms Detected in Carbapenem-Resistant Acinetobacter baumannii Clinical Isolates

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02143-15 ◽

2016 ◽

Vol 60 (3) ◽

pp. 1801-1818 ◽

Cited By ~ 29

Author(s):

Nabil Karah ◽

Chinmay Kumar Dwibedi ◽

Karin Sjöström ◽

Petra Edquist ◽

Anders Johansson ◽

...

Keyword(s):

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Resistance Genes ◽

Point Mutations ◽

Antibiotic Resistance Genes ◽

Opportunistic Pathogen ◽

Clinical Isolates ◽

Aminoglycoside Resistance ◽

Content Type ◽

Carbapenem Resistant

Acinetobacter baumanniihas emerged as an important opportunistic pathogen equipped with a growing number of antibiotic resistance genes. Our study investigated the molecular epidemiology and antibiotic resistance features of 28 consecutive carbapenem-resistant clinical isolates ofA. baumanniicollected throughout Sweden in 2012 and 2013. The isolates mainly belonged to clonal complexes (CCs) with an extensive international distribution, such as CC2 (n= 16) and CC25 (n= 7). Resistance to carbapenems was related toblaOXA-23(20 isolates),blaOXA-24/40-like(6 isolates),blaOXA-467(1 isolate), and ISAba1-blaOXA-69(1 isolate). Ceftazidime resistance was associated withblaPER-7in the CC25 isolates. Two classical point mutations were responsible for resistance to quinolones in all the isolates. Isolates with high levels of resistance to aminoglycosides carried the 16S rRNA methylasearmAgene. The isolates also carried a variety of genes encoding aminoglycoside-modifying enzymes. Several novel structures involved in aminoglycoside resistance were identified, including Tn6279, ΔTn6279, Ab-ST3-aadB, and different assemblies of Tn6020and TnaphA6. Importantly, a number of circular forms related to the IS26or ISAba125composite transposons were detected. The frequent occurrence of these circular forms in the populations of several isolates indicates a potential role of these circular forms in the dissemination of antibiotic resistance genes.

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Uropathogenic Escherichia coli in the Urine Samples of Iranian Dogs: Antimicrobial Resistance Pattern and Distribution of Antibiotic Resistance Genes

BioMed Research International ◽

10.1155/2017/4180490 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Amirhossein Yousefi ◽

Saam Torkan

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Antimicrobial Resistance ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Urine Samples ◽

Disk Diffusion ◽

Resistance Pattern ◽

E Coli ◽

Tract Infections

Resistant uropathogenic Escherichia coli is the most common cause of urinary tract infections in dogs. The present research was done to study the prevalence rate and antimicrobial resistance properties of UPEC strains isolated from healthy dogs and those which suffered from UTIs. Four-hundred and fifty urine samples were collected and cultured. E. coli-positive strains were subjected to disk diffusion and PCR methods. Two-hundred out of 450 urine samples (44.4%) were positive for E. coli. Prevalence of E. coli in healthy and infected dogs was 28% and 65%, respectively. Female had the higher prevalence of E. coli (P=0.039). Marked seasonality was also observed (P=0.024). UPEC strains had the highest levels of resistance against gentamicin (95%), ampicillin (85%), amikacin (70%), amoxicillin (65%), and sulfamethoxazole-trimethoprim (65%). We found that 21.50% of UPEC strains had simultaneously resistance against more than 10 antibiotics. Aac(3)-IV (77%), CITM (52.5%), tetA (46.5%), and sul1 (40%) were the most commonly detected antibiotic resistance genes. Findings showed considerable levels of antimicrobial resistance among UPEC strains of Iranian dogs. Rapid identification of infected dogs and their treatment based on the results of disk diffusion can control the risk of UPEC strains.

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Detection and prevalence of antimicrobial resistance genes in Campylobacter spp. isolated from chickens and humans

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v84i1.1411 ◽

2017 ◽

Vol 84 (1) ◽

Cited By ~ 13

Author(s):

Samantha Reddy ◽

Oliver T. Zishiri

Keyword(s):

Antibiotic Resistance ◽

Antimicrobial Resistance ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Antibiotic Resistance Genes ◽

Quinolone Resistance ◽

Campylobacter Coli ◽

Antimicrobial Resistance Genes ◽

Campylobacter Spp ◽

Clinical Cases

Campylobacter spp. are common pathogenic bacteria in both veterinary and human medicine. Infections caused by Campylobacter spp. are usually treated using antibiotics. However, the injudicious use of antibiotics has been proven to spearhead the emergence of antibiotic resistance. The purpose of this study was to detect the prevalence of antibiotic resistance genes in Campylobacter spp. isolated from chickens and human clinical cases in South Africa. One hundred and sixty one isolates of Campylobacter jejuni and Campylobacter coli were collected from chickens and human clinical cases and then screened for the presence of antimicrobial resistance genes. We observed a wide distribution of the tetO gene, which confers resistance to tetracycline. The gyrA genes that are responsible quinolone resistance were also detected. Finally, our study also detected the presence of the blaOXA-61, which is associated with ampicillin resistance. There was a higher (p < 0.05) prevalence of the studied antimicrobial resistance genes in chicken faeces compared with human clinical isolates. The tetO gene was the most prevalent gene detected, which was isolated at 64% and 68% from human and chicken isolates, respectively. The presence of gyrA genes was significantly (p < 0.05) associated with quinolone resistance. In conclusion, this study demonstrated the presence of gyrA (235 bp), gyrA (270 bp), blaOXA-61 and tetO antimicrobial resistance genes in C. jejuni and C. coli isolated from chickens and human clinical cases. This indicates that Campylobacter spp. have the potential of resistance to a number of antibiotic classes.

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