scholarly journals Whole Genome Sequencing of Aggregatibacter actinomycetemcomitans Cultured from Blood Stream Infections Reveals Three Major Phylogenetic Groups Including a Novel Lineage Expressing Serotype a Membrane O Polysaccharide

Pathogens ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 256 ◽  
Author(s):  
Signe Nedergaard ◽  
Carl M. Kobel ◽  
Marie B. Nielsen ◽  
Rikke T. Møller ◽  
Anne B. Jensen ◽  
...  

Twenty-nine strains of Aggregatibacter actinomycetemcomitans cultured from blood stream infections in Denmark were characterised. Serotyping was unremarkable, with almost equal proportions of the three major types plus a single serotype e strain. Whole genome sequencing positioned the serotype e strain outside the species boundary; moreover, one of the serotype a strains was unrelated to other strains of the major serotypes and to deposited sequences in the public databases. We identified five additional strains of this type in our collections. The particularity of the group was corroborated by phylogenetic analysis of concatenated core genes present in all strains of the species, and by uneven distribution of accessory genes only present in a subset of strains. Currently, the most accurate depiction of A. actinomycetemcomitans is a division into three lineages that differ in genomic content and competence for transformation. The clinical relevance of the different lineages is not known, and even strains excluded from the species sensu stricto can cause serious human infections. Serotyping is insufficient for characterisation, and serotypes a and e are not confined to specific lineages.

2021 ◽  
Vol 11 ◽  
Author(s):  
Angelica Bianco ◽  
Loredana Capozzi ◽  
Maria Rosa Monno ◽  
Laura Del Sambro ◽  
Viviana Manzulli ◽  
...  

Members of the Bacillus cereus group are spore-forming organisms commonly associated with food poisoning and intestinal infections. Moreover, some strains of the group (i.e., B. cereus sensu stricto and Bacillus thuringiensis) can cause bacteremia in humans, mainly in immunocompromised individuals. Here we performed the genetic characterization of 17 human clinical strains belonging to B. cereus group isolated from blood culture. The whole-genome sequencing (WGS) revealed that the isolates were closely related to B. cereus sensu stricto and B. thuringiensis–type strain. Multilocus sequence typing analysis performed on the draft genome revealed the genetic diversity of our isolates, which were assigned to different sequence types. Based on panC nucleotide sequence, the isolates were grouped in the phylogenetic groups III and IV. The NHE, cer, and inhA gene cluster, entA, entFM, plcA, and plcB, were the most commonly detected virulence genes. Although we did not assess the ability to generate biofilm by phenotypic tests, we verified the prevalence of biofilm associated genes using an in silico approach. A high prevalence of pur gene cluster, xerC, clpY, codY, tasA, sipW, sinI, and sigB genes, was found. Genes related to the resistance to penicillin, trimethoprim, and ceftriaxone were identified in most of the isolates. Intriguingly, the majority of these virulence and AMR genes appeared to be evenly distributed among B. cereus s.s. isolates, as well as closely related to B. thuringiensis isolates. We showed the WGS represents a good approach to rapidly characterize B. cereus group strains, being able to give useful information about genetic epidemiology, the presence of virulence and antimicrobial genes, and finally about the potential hazard related to this underestimated risk.


2018 ◽  
Vol 57 (7) ◽  
pp. 905-908 ◽  
Author(s):  
David New ◽  
Alicia G Beukers ◽  
Sarah E Kidd ◽  
Adam J Merritt ◽  
Kerry Weeks ◽  
...  

AbstractWhole genome sequencing (WGS) was used to demonstrate the wide genetic variability within Sporothrix schenckii sensu lato and establish that there are two main species of Sporothrix within Australian clinical isolates—S. schenckii sensu stricto and Sporothrix globosa. We also demonstrated southwest Western Australia contained genetically similar S. schenckii ss strains that are distinct from strains isolated in the eastern and northern states of Australia. Some genetic clustering by region was also noted for northern NSW, Queensland, and Northern Territory. Phylogenetic analysis of WGS data provided greater phylogenetic resolution compared to analysis of the calmodulin gene alone.


2016 ◽  
Vol 4 (6) ◽  
Author(s):  
Claudia Carolina Carbonari ◽  
Nahuel Fittipaldi ◽  
Sarah Teatero ◽  
Taryn B. T. Athey ◽  
Luis Pianciola ◽  
...  

Shiga toxin-producing Escherichia coli strains are worldwide associated with sporadic human infections and outbreaks. In this work, we report the availability of high-quality draft whole-genome sequences for 19 O157:H7 strains isolated in Argentina.


2020 ◽  
Vol 8 (6) ◽  
pp. 855 ◽  
Author(s):  
Alexandra Irrgang ◽  
Natalie Pauly ◽  
Bernd-Alois Tenhagen ◽  
Mirjam Grobbel ◽  
Annemarie Kaesbohrer ◽  
...  

Resistance to carbapenems is a severe threat to human health. These last resort antimicrobials are indispensable for the treatment of severe human infections with multidrug-resistant Gram-negative bacteria. In accordance with their increasing medical impact, carbapenemase-producing Enterobacteriaceae (CPE) might be disseminated from colonized humans to non-human reservoirs (i.e., environment, animals, food). In Germany, the occurrence of CPE in livestock and food has been systematically monitored since 2016. In the 2019 monitoring, an OXA-48-producing E. coli (19-AB01443) was recovered from a fecal sample of a fattening pig. Phenotypic resistance was confirmed by broth microdilution and further characterized by PFGE, conjugation, and combined short-/long-read whole genome sequencing. This is the first detection of this resistance determinant in samples from German meat production. Molecular characterization and whole-genome sequencing revealed that the blaOXA-48 gene was located on a common pOXA-48 plasmid-prototype. This plasmid-type seems to be globally distributed among various bacterial species, but it was frequently associated with clinical Klebsiella spp. isolates. Currently, the route of introduction of this plasmid/isolate combination into the German pig production is unknown. We speculate that due to its strong correlation with human isolates a transmission from humans to livestock has occurred.


eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Thomas R Connor ◽  
Clare R Barker ◽  
Kate S Baker ◽  
François-Xavier Weill ◽  
Kaisar Ali Talukder ◽  
...  

Shigella flexneri is the most common cause of bacterial dysentery in low-income countries. Despite this, S. flexneri remains largely unexplored from a genomic standpoint and is still described using a vocabulary based on serotyping reactions developed over half-a-century ago. Here we combine whole genome sequencing with geographical and temporal data to examine the natural history of the species. Our analysis subdivides S. flexneri into seven phylogenetic groups (PGs); each containing two-or-more serotypes and characterised by distinct virulence gene complement and geographic range. Within the S. flexneri PGs we identify geographically restricted sub-lineages that appear to have persistently colonised regions for many decades to over 100 years. Although we found abundant evidence of antimicrobial resistance (AMR) determinant acquisition, our dataset shows no evidence of subsequent intercontinental spread of antimicrobial resistant strains. The pattern of colonisation and AMR gene acquisition suggest that S. flexneri has a distinct life-cycle involving local persistence.


2019 ◽  
Vol 82 (8) ◽  
pp. 1398-1404 ◽  
Author(s):  
RENATE BOSS ◽  
JOERG HUMMERJOHANN

ABSTRACT Shiga toxin–producing Escherichia coli (STEC) strains are often found in food and cause human infections. Although STEC O157:H7 is most often responsible for human disease, various non-O157 subtypes have caused individual human infections or outbreaks. The importance of STEC serogroup typing is decreasing while detection of virulence gene patterns has become more relevant. Whole genome sequencing (WGS) reveals the entire spectrum of pathogen information, such as toxin variant, serotype, sequence type, and virulence factors. Flour has not been considered as a vector for STEC; however, this product has been associated with several STEC outbreaks in the last decade. Flour is a natural product, and milling does not include a germ-reducing step. Flour is rarely eaten raw, but the risks associated with the consumption of unbaked dough are probably underestimated. The aim of this study was to determine the prevalence of STEC in flour samples (n = 93) collected from Swiss markets and to fully characterize the isolates by PCR assay and WGS. The prevalence of STEC in these flour samples was 10.8% as indicated by PCR, and a total of 10 STEC strains were isolated (two flour samples were positive for two STEC subtypes). We found one stx2-positve STEC isolate belonging to the classic serogroups frequently associated with outbreaks that could potentially cause severe disease. However, we also found several other common or less common STEC subtypes with diverse virulence patterns. Our results reveal the benefits of WGS as a characterization tool and that flour is a potentially and probably underestimated source for STEC infections in humans.


2022 ◽  
Vol 12 ◽  
Author(s):  
Paula Kurittu ◽  
Banafsheh Khakipoor ◽  
Jari Jalava ◽  
Jari Karhukorpi ◽  
Annamari Heikinheimo

Antimicrobial resistance (AMR) is a growing concern in public health, particularly for the clinically relevant extended-spectrum beta-lactamase (ESBL) and AmpC-producing Enterobacteriaceae. Studies describing ESBL-producing Escherichia coli clinical samples from Finland to the genomic level and investigation of possible zoonotic transmission routes are scarce. This study characterizes ESBL-producing E. coli from clinical samples in Finland using whole genome sequencing (WGS). Comparison is made between animal, food, and environmental sources in Finland to gain insight into potential zoonotic transmission routes and to recognize successful AMR genes, bacterial sequence types (STs), and plasmids. ESBL-producing E. coli isolates (n = 30) obtained from the Eastern Finland healthcare district between 2018 and 2020 underwent WGS and were compared to sequences from non-human and healthy human sources (n = 67) isolated in Finland between 2012 and 2018. A majority of the clinical isolates belonged to ST131 (n = 21; 70%), of which 19 represented O25:H4 and fimH30 allele, and 2 O16:H5 and fimH41 allele. Multidrug resistance was common, and the most common bla gene identified was blaCTX–M–27 (n = 14; 47%) followed by blaCTX–M–15 (n = 10; 33%). blaCTX–M–27 was identified in 13 out of 21 isolates representing ST131, with 12 isolates belonging to a recently discovered international E. coli ST131 C1-M27 subclade. Isolates were found to be genetically distinct from non-human sources with core genome multilocus sequence typing based analysis. Most isolates (n = 26; 87%) possessed multiple replicons, with IncF family plasmids appearing in 27 (90%) and IncI1 in 5 (17%) isolates. IncF[F1:A2:B20] replicon was identified in 11, and IncF[F-:A2:B20] in 4 isolates. The results indicate the ST131-C1-M27 clade gaining prevalence in Europe and provide further evidence of the concerning spread of this globally successful pathogenic clonal group. This study is the first to describe ESBL-producing E. coli in human infections with WGS in Finland and provides important information on global level of the spread of ESBL-producing E. coli belonging to the C1-M27 subclade. The results will help guide public health actions and guide future research.


2018 ◽  
Vol 6 (19) ◽  
Author(s):  
Marie Reinhardt ◽  
Jens A. Hammerl ◽  
Stefan Hertwig

ABSTRACT We report here the draft genome sequences of 10 Yersinia pseudotuberculosis isolates recovered from tonsils of wild boars hunted between 2015 and 2016 in Germany. Whole-genome sequencing and bioinformatic analyses were performed to assess the diversity of Y. pseudotuberculosis , which may result in human infections caused by the consumption of game meat.


2020 ◽  
Vol 8 (9) ◽  
pp. 1393
Author(s):  
Giuseppe Aprea ◽  
Silvia Scattolini ◽  
Daniela D’Angelantonio ◽  
Alexandra Chiaverini ◽  
Valeria Di Lollo ◽  
...  

Hepatitis E virus (HEV) is an emergent zoonotic pathogen, causing worldwide acute and chronic hepatitis in humans. HEV comprises eight genotypes and several subtypes. HEV genotypes 3 and 4 (HEV3 and HEV4) are zoonotic. In Italy, the most part of HEV infections (80%) is due to autochthonous HEV3 circulation of the virus, and the key role played by wild animals is generally accepted. Abruzzo is an Italian region officially considered an HEV “hot spot”, with subtype HEV3-c being up to now the only one reported among wild boars. During the year 2018–2019, a group of wild boars in Abruzzo were screened for HEV; positive RNA liver samples were subjected to HEV characterization by using the whole genome sequencing (WGS) approach methodology. This represents the first report about the detection of HEV-3 subtypes e and f in the wild boar population in this area. Since in Italy human infections from HEV 3-e and f have been associated with pork meat consumption, our findings deserve more in-depth analysis with the aim of evaluating any potential correlation between wild animals, the pork chain production and HEV human infections.


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