scholarly journals Genomic and temporal analyses of Mycobacterium bovis in southern Brazil

2021 ◽  
Vol 7 (5) ◽  
Author(s):  
Rudielle de Arruda Rodrigues ◽  
Flábio Ribeiro Araújo ◽  
Alberto Martín Rivera Dávila ◽  
Rodrigo Nestor Etges ◽  
Julian Parkhill ◽  
...  

Mycobacterium bovis is a causal agent of bovine tuberculosis (bTB), one of the most important diseases currently facing the cattle industry worldwide. Tracing the source of M. bovis infections of livestock is an important tool for understanding the epidemiology of bTB and defining control/eradication strategies. In this study, whole genome sequencing (WGS) of 74 M . bovis isolates sourced from naturally infected cattle in the State of Rio Grande do Sul (RS), southern Brazil, was used to evaluate the population structure of M. bovis in the region, identify potential transmission events and date the introduction of clonal complex (CC) European 2 (Eu2). In silico spoligotyping identified 11 distinct patterns including four new profiles and two CCs, European 1 (Eu1) and Eu2. The analyses revealed a high level of genetic diversity in the majority of herds and identified putative transmission clusters that suggested that within- and between-herd transmission is occurring in RS. In addition, a comparison with other published M. bovis isolates from Argentina, Brazil, Paraguay and Uruguay demonstrated some evidence for a possible cross-border transmission of CC Eu1 into RS from Uruguay or Argentina. An estimated date for the introduction of CC Eu2 into RS in the middle of the 19th century correlated with the historical introduction of cattle into RS to improve existing local breeds. These findings contribute to the understanding of the population structure of M. bovis in southern Brazil and highlight the potential of WGS in surveillance and helping to identify bTB transmission.

2021 ◽  
Vol 7 (5) ◽  
Author(s):  
Gizat Almaw ◽  
Getnet Abie Mekonnen ◽  
Adane Mihret ◽  
Abraham Aseffa ◽  
Hawult Taye ◽  
...  

Bovine tuberculosis (bTB) is endemic in cattle in Ethiopia, a country that hosts the largest national cattle herd in Africa. The intensive dairy sector, most of which is peri-urban, has the highest prevalence of disease. Previous studies in Ethiopia have demonstrated that the main cause is Mycobacterium bovis , which has been investigated using conventional molecular tools including deletion typing, spoligotyping and Mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR). Here we use whole-genome sequencing to examine the population structure of M. bovis in Ethiopia. A total of 134 M . bovis isolates were sequenced including 128 genomes from 85 mainly dairy cattle and six genomes isolated from humans, originating from 12 study sites across Ethiopia. These genomes provided a good representation of the previously described population structure of M. bovis , based on spoligotyping and demonstrated that the population is dominated by the clonal complexes African 2 (Af2) and European 3 (Eu3). A range of within-host diversity was observed amongst the isolates and evidence was found for both short- and long-distance transmission. Detailed analysis of available genomes from the Eu3 clonal complex combined with previously published genomes revealed two distinct introductions of this clonal complex into Ethiopia between 1950 and 1987, likely from Europe. This work is important to help better understand bTB transmission in cattle in Ethiopia and can potentially inform national strategies for bTB control in Ethiopia and beyond.


2020 ◽  
Vol 6 (8) ◽  
Author(s):  
Joseph Crispell ◽  
Sophie Cassidy ◽  
Kevin Kenny ◽  
Guy McGrath ◽  
Susan Warde ◽  
...  

Control of bovine tuberculosis (bTB), caused by Mycobacterium bovis , in the Republic of Ireland costs €84 million each year. Badgers are recognized as being a wildlife source for M. bovis infection of cattle. Deer are thought to act as spillover hosts for infection; however, population density is recognized as an important driver in shifting their epidemiological role, and deer populations across the country have been increasing in density and range. County Wicklow represents one specific area in the Republic of Ireland with a high density of deer that has had consistently high bTB prevalence for over a decade, despite control operations in both cattle and badgers. Our research used whole-genome sequencing of M. bovis sourced from infected cattle, deer and badgers in County Wicklow to evaluate whether the epidemiological role of deer could have shifted from spillover host to source. Our analyses reveal that cattle and deer share highly similar M. bovis strains, suggesting that transmission between these species is occurring in the area. In addition, the high level of diversity observed in the sampled deer population suggests deer may be acting as a source of infection for local cattle populations. These findings have important implications for the control and ultimate eradication of bTB in Ireland.


Author(s):  
Emeli Månsson ◽  
Thor Bech Johannesen ◽  
Åsa Nilsdotter-Augustinsson ◽  
Bo Söderquist ◽  
Marc Stegger

There is increased awareness of the worldwide spread of specific epidemic multidrug-resistant (MDR) lineages of the human commensal Staphylococcus epidermidis . Here, using bioinformatic analyses accounting for population structure, we determined genomic traits (genes, SNPs and k-mers) that distinguish S. epidermidis causing prosthetic-joint infections (PJIs) from commensal isolates from nares, by analysing whole-genome sequencing data from S. epidermidis from PJIs prospectively collected over 10 years in Sweden, and contemporary S. epidermidis from the nares of patients scheduled for arthroplasty surgery. Previously suggested virulence determinants and the presence of genes and mutations linked to antimicrobial resistance (AMR) were also investigated. Publicly available S. epidermidis sequences were used for international extrapolation and validation of findings. Our data show that S. epidermidis causing PJIs differed from nasal isolates not by virulence but by traits associated with resistance to compounds used in prevention of PJIs: β-lactams, aminoglycosides and chlorhexidine. Almost a quarter of the PJI isolates did not belong to any of the previously described major nosocomial lineages, but the AMR-related traits were also over-represented in these isolates, as well as in international S. epidermidis isolates originating from PJIs. Genes previously associated with virulence in S. epidermidis were over-represented in individual lineages, but failed to reach statistical significance when adjusted for population structure. Our findings suggest that the current strategies for prevention of PJIs select for nosocomial MDR S. epidermidis lineages that have arisen from horizontal gene transfer of AMR-related traits into multiple genetic backgrounds.


Author(s):  
Aleksandra Trościańczyk ◽  
Aneta Nowakiewicz ◽  
Sebastian Gnat ◽  
Dominik Łagowski ◽  
Marcelina Osińska ◽  
...  

Introduction. The possible transfer of antimicrobial resistance genes between Enterococcus faecium isolates from humans and different animal species, including those not covered by monitoring programs (e.g. pet and wildlife), poses a serious threat to public health. Hypothesis/Gap Statement. Little is known about occurrence and mechanisms of phenomenon of multidrug resistance of E. faecium isolated from various host species in Poland. Aim. The aim of the study was to characterize multidrug-resistant E. faecium isolated from humans and animals (livestock, pets and wildlife) in terms of the occurrence of genetic markers determining resistance. Methodology. Bacterial isolates were tested for phenotypic resistance and the presence of genes encoding resistance to macrolides, tetracycline, aminoglycosides, aminocyclitols and phenicols as well as efflux pump (emeA), resolvase (tndX) and integrase (Int-Tn) genes. The quinolone resistance-determining regions of gyrA and parC were sequenced. Results. Human isolates of E. faecium were characterized by high-level resistance to: ciprofloxacin, enrofloxacin, erythromycin (100 %), as well, as aminoglycosides resistance (kanamycin – 100%, streptomycin – 78 %, gentamicin – 78%). Regardless of the animal species, high level of resistance of E. faecium to tetracycline (from 88–100 %), erythromycin (from 82–94 %) and kanamycin (from 36–100 %) was observed. All E. faecium isolates from wildlife were resistant to fluoroquinolones. However, full susceptibility to vancomycin was observed in all isolates tested. Phenotypic antimicrobial resistance of E. faecium was identified in the presence of the following resistance genes: erm(B) (70%), msr(A) (50 %), tet(L) (35 %), tet(K) (34 %), tet(M) (76 %), aac(6’)-Ie-aph(2″)-Ia (25%), ant(6)-Ia (31%), aph(3)-IIIa (68 %), (tndX) (23 %), and integrase gene (Int-Tn) (34 %). A correlation between an amino acid substitution at positions 83 and 87 of gyrA and position 80 of parC and the high-level fluoroquinolone resistance in E. faecium has been observed as well. Conclusion. The level and range of antimicrobial resistance and the panel of resistance determinants is comparable between E. faecium isolates, despite host species.


2013 ◽  
Vol 63 (Pt_10) ◽  
pp. 3777-3781 ◽  
Author(s):  
Christine Martineau ◽  
Céline Villeneuve ◽  
Florian Mauffrey ◽  
Richard Villemur

A budding prosthecate bacterial strain, designated NL23T, was isolated from a methanol-fed denitrification system treating seawater at the Montreal Biodome, Canada. Phylogenetic analysis based on 16S rRNA (rRNA) gene sequences showed that the strain was affiliated with the genus Hyphomicrobium of the Alphaproteobacteria and was most closely related to Hyphomicrobium zavarzinii with 99.4 % sequence similarity. Despite this high level of 16S rRNA gene sequence similarity, DNA–DNA hybridization assays showed that strain NL23T was only distantly related to H. zavarzinii ZV-622T (12 %). Strain NL23T grew aerobically, but also had the capacity to grow under denitrifying conditions in the presence of nitrate without nitrite accumulation. Growth occurred at pH 7.0–9.5, with 0–1 % NaCl and at temperatures of 15–35 °C. Major fatty acids were C18 : 1ω7c or ω6c (84.6 %) and C18 : 0 (8.5 %), and major quinones were Q8 (5 %) and Q9 (95 %). The complete genome of the strain was sequenced and showed a DNA G+C content of 63.8 mol%. Genome analysis predicted open reading frames (ORF) encoding the key enzymes of the serine pathway as well as enzymes involved in methylotrophy. Also, ORF encoding a periplasmic nitrate reductase (Nap), a nitrite reductase (Nir), a nitric oxide reductase (Nor) and a nitrous oxide reductase (Nos) were identified. Our results support that strain NL23T represents a novel species within the genus Hyphomicrobium , for which the name Hyphomicrobium nitrativorans sp. nov. is proposed. The type strain is NL23T ( = ATCC BAA-2476T = LMG 27277T).


Microbiology ◽  
2020 ◽  
Vol 166 (8) ◽  
pp. 695-706 ◽  
Author(s):  
Kevin H. Martin ◽  
Grace I. Borlee ◽  
William H. Wheat ◽  
Mary Jackson ◽  
Bradley R. Borlee

Biofilm-associated infections are difficult to eradicate because of their ability to tolerate antibiotics and evade host immune responses. Amoebae and/or their secreted products may provide alternative strategies to inhibit and disperse biofilms on biotic and abiotic surfaces. We evaluated the potential of five predatory amoebae – Acanthamoeba castellanii, Acanthamoeba lenticulata, Acanthamoeba polyphaga, Vermamoeba vermiformis and Dictyostelium discoideum – and their cell-free secretions to disrupt biofilms formed by methicillin-resistant Staphylococcus aureus (MRSA) and Mycobacterium bovis . The biofilm biomass produced by MRSA and M. bovis was significantly reduced when co-incubated with A. castellanii, A. lenticulata and A. polyphaga, and their corresponding cell-free supernatants (CFS). Acanthamoeba spp. generally produced CFS that mediated biofilm dispersal rather than directly killing the bacteria; however, A. polyphaga CFS demonstrated active killing of MRSA planktonic cells when the bacteria were present at low concentrations. The active component(s) of the A. polyphaga CFS is resistant to freezing, but can be inactivated to differing degrees by mechanical disruption and exposure to heat. D. discoideum and its CFS also reduced preformed M. bovis biofilms, whereas V. vermiformis only decreased M. bovis biofilm biomass when amoebae were added. These results highlight the potential of using select amoebae species or their CFS to disrupt preformed bacterial biofilms.


Microbiology ◽  
2020 ◽  
Vol 166 (11) ◽  
pp. 1074-1087
Author(s):  
Kishore Reddy Venkata Thappeta ◽  
Kristin Ciezki ◽  
Nydia Morales-Soto ◽  
Shane Wesener ◽  
Heidi Goodrich-Blair ◽  
...  

Xenorhabdus species are bacterial symbionts of Steinernema nematodes and pathogens of susceptible insects. Different species of Steinernema nematodes carrying specific species of Xenorhabdus can invade the same insect, thereby setting up competition for nutrients within the insect environment. While Xenorhabdus species produce both diverse antibiotic compounds and prophage-derived R-type bacteriocins (xenorhabdicins), the functions of these molecules during competition in a host are not well understood. Xenorhabdus bovienii (Xb-Sj), the symbiont of Steinernema jollieti, possesses a remnant P2-like phage tail cluster, xbp1, that encodes genes for xenorhabdicin production. We show that inactivation of either tail sheath (xbpS1) or tail fibre (xbpH1) genes eliminated xenorhabdicin production. Preparations of Xb-Sj xenorhabdicin displayed a narrow spectrum of activity towards other Xenorhabdus and Photorhabdus species. One species, Xenorhabdus szentirmaii (Xsz-Sr), was highly sensitive to Xb-Sj xenorhabdicin but did not produce xenorhabdicin that was active against Xb-Sj. Instead, Xsz-Sr produced high-level antibiotic activity against Xb-Sj when grown in complex medium and lower levels when grown in defined medium (Grace’s medium). Conversely, Xb-Sj did not produce detectable levels of antibiotic activity against Xsz-Sr. To study the relative contributions of Xb-Sj xenorhabdicin and Xsz-Sr antibiotics in interspecies competition in which the respective Xenorhabdus species produce antagonistic activities against each other, we co-inoculated cultures with both Xenorhabdus species. In both types of media Xsz-Sr outcompeted Xb-Sj, suggesting that antibiotics produced by Xsz-Sr determined the outcome of the competition. In contrast, Xb-Sj outcompeted Xsz-Sr in competitions performed by co-injection in the insect Manduca sexta, while in competition with the xenorhabdicin-deficient strain (Xb-Sj:S1), Xsz-Sr was dominant. Thus, xenorhabdicin was required for Xb-Sj to outcompete Xsz-Sr in a natural host environment. These results highlight the importance of studying the role of antagonistic compounds under natural biological conditions.


2021 ◽  
Vol 7 (12) ◽  
Author(s):  
Quynh Nguyen ◽  
To Thi Nguyen Nguyen ◽  
Phuong Pham ◽  
Vinh Chau ◽  
Lan Phu Huong Nguyen ◽  
...  

Extra-intestinal pathogenic Escherichia coli (ExPEC) ST1193, a globally emergent fluoroquinolone-resistant clone, has become an important cause of bloodstream infections (BSIs) associated with significant morbidity and mortality. Previous studies have reported the emergence of fluoroquinolone-resistant ExPEC ST1193 in Vietnam; however, limited data exist regarding the genetic structure, antimicrobial resistance (AMR) determinants and transmission dynamics of this pandemic clone. Here, we performed genomic and phylogenetic analyses of 46 ST1193 isolates obtained from BSIs and healthy individuals in Ho Chi Minh City, Vietnam, to investigate the pathogen population structure, molecular mechanisms of AMR and potential transmission patterns. We further examined the phylogenetic structure of ST1193 isolates in a global context. We found that the endemic E. coli ST1193 population was heterogeneous and highly dynamic, largely driven by multiple strain importations. Several well-supported phylogenetic clusters (C1–C6) were identified and associated with distinct bla CTX-M variants, including bla CTXM-27 (C1–C3, C5), bla CTXM-55 (C4) and bla CTXM-15 (C6). Most ST1193 isolates were multidrug-resistant and carried an extensive array of AMR genes. ST1193 isolates also exhibited the ability to acquire further resistance while circulating in Vietnam. There were phylogenetic links between ST1193 isolates from BSIs and healthy individuals, suggesting these organisms may both establish long-term colonization in the human intestinal tract and induce infections. Our study uncovers factors shaping the population structure and transmission dynamics of multidrug-resistant ST1193 in Vietnam, and highlights the urgent need for local One Health genomic surveillance to capture new emerging ExPEC clones and to better understand the origins and transmission patterns of these pathogens.


2021 ◽  
Vol 7 (10) ◽  
Author(s):  
Ana C. Reis ◽  
Mónica V. Cunha

Animal tuberculosis (TB) is an emergent disease caused by Mycobacterium bovis , one of the animal-adapted ecotypes of the Mycobacterium tuberculosis complex (MTC). In this work, whole-genome comparative analyses of 70 M . bovis were performed to gain insights into the pan-genome architecture. The comparison across M. bovis predicted genome composition enabled clustering into the core- and accessory-genome components, with 2736 CDS for the former, while the accessory moiety included 3897 CDS, of which 2656 are restricted to one/two genomes only. These analyses predicted an open pan-genome architecture, with an average of 32 CDS added by each genome and show the diversification of discrete M. bovis subpopulations supported by both core- and accessory-genome components. The functional annotation of the pan-genome classified each CDS into one or several COG (Clusters of Orthologous Groups) categories, revealing ‘transcription’ (total average CDSs, n=258), ‘lipid metabolism and transport’ (n=242), ‘energy production and conversion’ (n=214) and ‘unknown function’ (n=876) as the most represented. The closer analysis of polymorphisms in virulence-related genes in a restrict group of M. bovis from a multi-host system enabled the identification of clade-monomorphic non-synonymous SNPs, illustrating clade-specific virulence landscapes and correlating with disease severity. This first comparative pan-genome study of a diverse collection of M. bovis encompassing all clonal complexes indicates a high percentage of accessory genes and denotes an open, dynamic non-conservative pan-genome structure, with high evolutionary potential, defying the canons of MTC biology. Furthermore, it shows that M. bovis can shape its virulence repertoire, either by acquisition and loss of genes or by SNP-based diversification, likely towards host immune evasion, adaptation and persistence.


2020 ◽  
Vol 2 (7) ◽  
Author(s):  
Damien Farrell ◽  
Joseph Crispell ◽  
Stephen V. Gordon

Mycobacterium bovis AF2122/97 is the reference strain for the bovine tuberculosis bacillus. Here we report an update to the M. bovis AF2122/97 genome annotation to reflect 616 new protein identifications that replace many of the old hypothetical coding sequences and proteins of unknown function in the genome. These changes integrate information from functional assignments of orthologous coding sequences in the Mycobacterium tuberculosis H37Rv genome. We have also added 69 additional new gene names.


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