| 1. |
- Sjödin, Kotryna Simonyté, et al.
(författare)
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Targeting the gut-lung axis by synbiotic feeding to infants in a randomized controlled trial
- 2023
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Ingår i: BMC Biology. - : BioMed Central (BMC). - 1741-7007. ; 21:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Formula-fed infants are at increased risk of infections. Due to the cross-talk between the mucosal systems of the gastrointestinal and respiratory tracts, adding synbiotics (prebiotics and probiotics) to infant formula may prevent infections even at distant sites. Infants that were born full term and weaned from breast milk were randomized to prebiotic formula (fructo- and galactooligosaccharides) or the same prebiotic formula with Lactobacillus paracasei ssp. paracasei F19 (synbiotics) from 1 to 6 months of age. The objective was to examine the synbiotic effects on gut microbiota development. RESULTS: Fecal samples collected at ages 1, 4, 6, and 12 months were analyzed using 16S rRNA gene sequencing and a combination of untargeted gas chromatography-mass spectrometry/liquid chromatography-mass spectrometry. These analyses revealed that the synbiotic group had a lower abundance of Klebsiella, a higher abundance of Bifidobacterium breve compared to the prebiotic group, and increases in the anti-microbial metabolite d-3-phenyllactic acid. We also analyzed the fecal metagenome and antibiotic resistome in the 11 infants that had been diagnosed with lower respiratory tract infection (cases) and 11 matched controls using deep metagenomic sequencing. Cases with lower respiratory tract infection had a higher abundance of Klebsiella species and antimicrobial resistance genes related to Klebsiella pneumoniae, compared to controls. The results obtained using 16S rRNA gene amplicon and metagenomic sequencing were confirmed in silico by successful recovery of the metagenome-assembled genomes of the bacteria of interest. CONCLUSIONS: This study demonstrates the additional benefit of feeding specific synbiotics to formula-fed infants over prebiotics only. Synbiotic feeding led to the underrepresentation of Klebsiella, enrichment of bifidobacteria, and increases in microbial degradation metabolites implicated in immune signaling and in the gut-lung and gut-skin axes. Our findings support future clinical evaluation of synbiotic formula in the prevention of infections and associated antibiotic treatment as a primary outcome when breastfeeding is not feasible. TRIAL REGISTRATION: ClinicalTrials.gov NCT01625273. Retrospectively registered on 21 June 2012.
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| 2. |
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| 3. |
- Christensen, Andreas, 1987-
(författare)
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Capacities, Poincaré inequalities and gluing metric spaces.
- 2023
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis consists of an introduction, and one research paper with results related to potential theory both in the classical Euclidean setting, as well as in quite general metric spaces.The introduction contains a theoretical and historical background of some basic concepts, and their more modern generalisations to metric spaces developed in the last 30 years. By using upper gradients it is possible to define such notions as first order Sobolev spaces, p-harmonic functions and capacity on metric spaces. When generalising classical results to metric spaces, one often needs to impose some structure on the space by making additional assumptions, such as a doubling condition and a Poincaré inequality.In the included research paper, we study a certain type of metric spaces called bow-ties, which consist of two metric spaces glued together at a single designated point. For a doubling measure μ, we characterise when μ supports a Poincar´e inequality on the bow-tie, in terms of Poincaré inequalities on the separate parts together with a variational p-capacity condition and a quasiconvexity-type condition. The variational p-capacity condition is then characterised by a sharp measure decay condition at the designated point.We also study the special case when the bow-tie consists of the positive and negative hyperquadrants in Rn, equipped with a radial doubling measure. In this setting, we characterise the validity of the p-Poincaré inequality in various ways, and then provide a formula for the variational p-capacity of annuli centred at the origin.i
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| 4. |
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| 5. |
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| 6. |
- Eriksson, Karolina Ida Anna, et al.
(författare)
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Association between Legionella species and humic substances during early summer in the northern Baltic Sea
- 2023
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Ingår i: Frontiers in Marine Science. - : Frontiers Media S.A.. - 2296-7745. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Climate change is projected to cause alterations in northern coastal systems, including humification and intensified nutrient loads, which can lead to ecosystem imbalances and establishment of new bacterial species. Several potential pathogens, such as different species of Legionella, hide in the environment between infections, some by living inside protozoan host cells. Knowledge about the occurrence of Legionella in natural waters is missing, which disable risk assessments of exposure. We performed a study of the species diversity of Legionella in the northern Baltic Sea (Gulf of Bothnia) during early summer to map their occurrence and to identify possible environmental drivers. We detected Legionella and potential protozoan hosts along gradients of the Gulf of Bothnia. We also for the first time present third generation full-length 16S rRNA amplicon sequencing (Nanopore) to resolve environmental species classification of Legionella, with a method suitable to study all bacteria. Our data show that full length 16S rRNA sequences is sufficient to resolve Legionella while the standard short Illumina sequences did not capture the entire diversity. For accurate species classification of Legionella, harmonization between the Nanopore classification methods is still needed and the bias toward the well-studied Legionella pneumophila need to be resolved. Different Legionella species occurred both in the Bothnian Sea and in the Bothnian Bay and their abundance were linked to humic substances and low salinity. The relative abundance of Legionella was higher in the humic-rich northern waters of the Bothnian Bay. The link between Legionella species and humic substances may be indirect via promotion of the heterotrophic microbial food web, allowing Legionella species and similar bacteria to establish. Humic substances are rich in iron, which has been shown crucial for growth of Legionella species and other pathogens. Considering climate change projections in this regional area, with increased humification and freshwater inflow, this bacterial niche containing potential pathogens might become more widespread in the future Baltic Sea. This study demonstrates the significance of DNA sequencing to monitor public health relevant bacteria like Legionella species in the environment. Including sequencing of bacteria and protozoa in the environmental monitoring programs could be used to identify ecosystem imbalances, which enable appropriate responses to emerging diseases.
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| 7. |
- Fracheboud, Yvan, et al.
(författare)
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The control of autumn senescence in European aspen
- 2009
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Ingår i: Plant Physiology. - : Oxford University Press (OUP). - 0032-0889 .- 1532-2548. ; 149:4, s. 1982-1991
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Tidskriftsartikel (refereegranskat)abstract
- The initiation, progression, and natural variation of autumn senescence in European aspen (Populus tremula) was investigated by monitoring chlorophyll degradation in (1) trees growing in natural stands and (2) cloned trees growing in a greenhouse under various light regimes. The main trigger for the initiation of autumn senescence in aspen is the shortening photoperiod, but there was a large degree of variation in the onset of senescence, both within local populations and among trees originating from different populations, where it correlated with the latitude of their respective origins. The variation for onset of senescence with a population was much larger than the variation of bud set. Once started, autumn senescence was accelerated by low temperature and longer nights, and clones that started to senescence late had a faster senescence. Bud set and autumn senescence appeared to be under the control of two independent critical photoperiods, but senescence could not be initiated until a certain time after bud set, suggesting that bud set and growth arrest are important for the trees to acquire competence to respond to the photoperiodic trigger to undergo autumn senescence. A timetable of events related to bud set and autumn senescence is presented.
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| 8. |
- Goormaghtigh, Frederic, et al.
(författare)
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Reassessing the Role of Type II Toxin-Antitoxin Systems in Formation of Escherichia coli Type II Persister Cells
- 2018
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Ingår i: mBio. - : American Society for Microbiology. - 2161-2129 .- 2150-7511. ; 9:3
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Tidskriftsartikel (refereegranskat)abstract
- Persistence is a reversible and low-frequency phenomenon allowing a subpopulation of a clonal bacterial population to survive antibiotic treatments. Upon removal of the antibiotic, persister cells resume growth and give rise to viable progeny. Type II toxin-antitoxin (TA) systems were assumed to play a key role in the formation of persister cells in Escherichia coli based on the observation that successive deletions of TA systems decreased persistence frequency. In addition, the model proposed that stochastic fluctuations of (p)ppGpp levels are the basis for triggering activation of TA systems. Cells in which TA systems are activated are thought to enter a dormancy state and therefore survive the antibiotic treatment. Using independently constructed strains and newly designed fluorescent reporters, we reassessed the roles of TA modules in persistence both at the population and single-cell levels. Our data confirm that the deletion of 10 TA systems does not affect persistence to ofloxacin or ampicillin. Moreover, microfluidic experiments performed with a strain reporting the induction of the yefM-yoeB TA system allowed the observation of a small number of type II persister cells that resume growth after removal of ampicillin. However, we were unable to establish a correlation between high fluorescence and persistence, since the fluorescence of persister cells was comparable to that of the bulk of the population and none of the cells showing high fluorescence were able to resume growth upon removal of the antibiotic. Altogether, these data show that there is no direct link between induction of TA systems and persistence to antibiotics. IMPORTANCE Within a growing bacterial population, a small subpopulation of cells is able to survive antibiotic treatment by entering a transient state of dormancy referred to as persistence. Persistence is thought to be the cause of relapsing bacterial infections and is a major public health concern. Type II toxin-antitoxin systems are small modules composed of a toxic protein and an antitoxin protein counteracting the toxin activity. These systems were thought to be pivotal players in persistence until recent developments in the field. Our results demonstrate that previous influential reports had technical flaws and that there is no direct link between induction of TA systems and persistence to antibiotics.
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| 9. |
- Haas, Julia Christa, et al.
(författare)
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Microbial community response to growing season and plant nutrient optimisation in a boreal Norway spruce forest
- 2018
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Ingår i: Soil Biology and Biochemistry. - : Elsevier. - 0038-0717 .- 1879-3428. ; 125, s. 197-209
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Tidskriftsartikel (refereegranskat)abstract
- Interactions between Norway spruce trees and bacteria and fungi in nutrient limited boreal forests can be beneficial for tree growth and fitness. Tree-level effects of anthropogenic nutrient addition have been well studied, however understanding of the long-term effects on the associated microbiota is limited. Here, we report on the sensitivity of microbial community composition to the growing season and nutrient additions. Highthroughput sequencing of the bacterial 16S rRNA gene and fungal ITS1 region was used to characterise changes in the microbial community after application of a complete mineral nutrient mixture for five and 25 years. The experiment was conducted using the Flakaliden forest research site in northern boreal Sweden and included naturally low nutrient control plots. Needle and fine root samples of Norway spruce were sampled in addition to bulk soil during one growing season to provide comprehensive insight into phyllosphere and belowground microbiota community changes. The phyllosphere microbiota was compositionally distinct from the belowground communities and phyllosphere diversity increased significantly over the growing season but was not influenced by the improved nutrient status of the trees. In both root and soil samples, alpha diversity of fungal, in particular ectomycorrhizal fungi (EMF), and bacterial communities increased after long-term nutrient optimisation, and with increasing years of treatment the composition of the fungal and bacterial communities changed toward a community with a higher relative abundance of nitrophilic EMF and bacterial species but did not cause complete loss of nitrophobic species from the ecosystem. From this, we conclude that 25 years of continuous nutrient addition to a boreal spruce stand increased phylotype richness and diversity of the microbiota in the soil, and at the root-soil interface, suggesting that long-term anthropogenic nutrient inputs can have positive effects on belowground biodiversity that may enhance ecosystem robustness. Future studies are needed to assess the impact of these changes to the microbiota on ecosystem carbon storage and nitrogen cycling in boreal forests.
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| 10. |
- Hägglund, Moa, et al.
(författare)
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Accounting for bacterial overlap between raw water communities and contaminating sources improves the accuracy of signature-based microbial source tracking
- 2018
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Ingår i: Frontiers in Microbiology. - : Frontiers Media S.A.. - 1664-302X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Microbial source tracking (MST) analysis is essential to identifying and mitigating the fecal pollution of water resources. The signature-based MST method uses a library of sequences to identify contaminants based on operational taxonomic units (OTUs) that are unique to a certain source. However, no clear guidelines for how to incorporate OTU overlap or natural variation in the raw water bacterial community into MST analyses exist. We investigated how the inclusion of bacterial overlap between sources in the library affects source prediction accuracy. To achieve this, large-scale sampling-including feces from seven species, raw sewage, and raw water samples from water treatment plants - was followed by 16S rRNA amplicon sequencing. The MST library was defined using three settings: (i) no raw water communities represented; (ii) raw water communities selected through clustering analysis; and (iii) local water communities collected across consecutive years. The results suggest that incorporating either the local background or representative bacterial composition improves MST analyses, as the results were positively correlated to measured levels of fecal indicator bacteria and the accuracy at which OTUs were assigned to the correct contamination source increased fourfold. Using the proportion of OTUs with high source origin probability, underpinning a contaminating signal, is a solid foundation in a framework for further deciphering and comparing contaminating signals derived in signature-based MST approaches. In conclusion, incorporating background bacterial composition of water in MST can improve mitigation efforts for minimizing the spread of pathogenic and antibiotic resistant bacteria into essential freshwater resources.
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| 11. |
- Karlsson, Edvin, et al.
(författare)
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The phylogeographic pattern of Francisella tularensis in Sweden indicates a Scandinavian origin of Eurosiberian tularaemia
- 2013
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Ingår i: Environmental Microbiology. - : Wiley. - 1462-2912 .- 1462-2920. ; 15:2, s. 634-645
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Tidskriftsartikel (refereegranskat)abstract
- Previous studies of the causative agent of tularaemia, Francisella tularensis have identified phylogeographic patterns suggestive of environmental maintenance reservoirs. To investigate the phylogeography of tularaemia in Sweden, we selected 163 clinical isolates obtained during 1995-2009 in 10 counties and sequenced one isolate's genome to identify new genetic markers. An improved typing scheme based on two indels and nine SNPs was developed using hydrolysis or TaqMan MGB probe assays. The results showed that much of the known global genetic diversity of F. tularensis subsp. holarctica is present in Sweden. Thirteen of the 163 isolates belonged to a new genetic group that is basal to all other known members of the major genetic clade B.I, which is spread across the Eurosiberian region. One hundred and twenty-five of the 163 Swedish isolates belonged to B.I, but individual clades' frequencies differed from county to county (P < 0.001). Subsequent analyses revealed a correlation between genotype variation over time and recurrent outbreaks at specific places, supporting the 'maintenance reservoir' environmental maintenance hypothesis. Most importantly, the findings reveal the presence of diverse source populations of F. tularensis subsp. holarctica in Sweden and suggest a historical spread of the disease from Scandinavia to other parts of Eurosiberia.
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| 12. |
- Lee, Hyoshin, et al.
(författare)
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Growth-phase-dependent gene expression profiling of poplar (Populus alba x Populus tremula var. glandulosa) suspension cells
- 2007
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Ingår i: Physiologia Plantarum. - : John Wiley & Sons. - 0031-9317 .- 1399-3054. ; 131:4, s. 599-613
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Tidskriftsartikel (refereegranskat)abstract
- Complex sequences of morphological and biochemical changes occur during the developmental course of a batch plant cell culture. However, little information is available about the changes in gene expression that could explain these changes, because of the difficulties involved in isolating specific cellular events or developmental phases in the overlapping phases of cell growth. In an attempt to obtain such information we have examined the global growth phase-dependent gene expression of poplar cells in suspension cultures by cDNA microarray analysis. Our results reveal that significant changes occur in the expression of genes with functions related to protein synthesis, cell cycling, hormonal responses and cell wall biosynthesis, as cultures progress from initiation to senescence, that are highly correlated with observed developmental and physiological changes in the cells. Genes encoding protein kinases, calmodulin and proteins involved in both ascorbate metabolism and water-limited stress responses also showed strong stage-specific expression patterns. Our report provides fundamental information on molecular mechanisms that control cellular changes throughout the developmental course of poplar cell cultures.
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| 13. |
- Myrtennäs, Kerstin, et al.
(författare)
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Genome sequence of Francisella Tularensis subspecies holarctica Strain FSC200, isolated from a child with Tularemia
- 2012
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Ingår i: Journal of Bacteriology. - : American Society for Microbiology. - 0021-9193 .- 1098-5530. ; 194:24, s. 6965-6966
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Tidskriftsartikel (refereegranskat)abstract
- Here we report the complete, accurate 1.89-Mb genome sequence of Francisella tularensis subsp. holarctica strain FSC200, isolated in 1998 in the Swedish municipality Ljusdal, which is in an area where tularemia is highly endemic. This genome is important because strain FSC200 has been extensively used for functional and genetic studies of Francisella and is well-characterized.
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| 14. |
- Rentoft, Matilda, et al.
(författare)
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A geographically matched control population efficiently limits the number of candidate disease-causing variants in an unbiased whole-genome analysis
- 2019
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203 .- 1932-6203. ; 14:3
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Tidskriftsartikel (refereegranskat)abstract
- Whole-genome sequencing is a promising approach for human autosomal dominant disease studies. However, the vast number of genetic variants observed by this method constitutes a challenge when trying to identify the causal variants. This is often handled by restricting disease studies to the most damaging variants, e. g. those found in coding regions, and overlooking the remaining genetic variation. Such a biased approach explains in part why the genetic causes of many families with dominantly inherited diseases, in spite of being included in whole-genome sequencing studies, are left unsolved today. Here we explore the use of a geographically matched control population to minimize the number of candidate disease-causing variants without excluding variants based on assumptions on genomic position or functional predictions. To exemplify the benefit of the geographically matched control population we apply a typical disease variant filtering strategy in a family with an autosomal dominant form of colorectal cancer. With the use of the geographically matched control population we end up with 26 candidate variants genome wide. This is in contrast to the tens of thousands of candidates left when only making use of available public variant datasets. The effect of the local control population is dual, it (1) reduces the total number of candidate variants shared between affected individuals, and more importantly (2) increases the rate by which the number of candidate variants are reduced as additional affected family members are included in the filtering strategy. We demonstrate that the application of a geographically matched control population effectively limits the number of candidate disease-causing variants and may provide the means by which variants suitable for functional studies are identified genome wide.
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| 15. |
- Sjödin, Andreas, 1976-
(författare)
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Populus transcriptomics : from noise to biology
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Mikromatriser handlar numera inte bara om att alstra genuttrycksdata i snabb takt, utan det är minst lika viktigt att effektivt ta hand om informationen efteråt. I den här avhandlingen presenteras ett arbetsflöde för att mäta, lagra och analysera genuttrycksdata i asp och poppel (Populus spp.). En Populus} mikromatrisdatabas - UPSC--BASE - tillgänglig för alla intresserade, utvecklades i syfte att samla in och lagra genuttrycksdata. Flertalet analysverktyg gjordes samtidigt tillgängliga, för att möjliggöra ett smidigt arbetsflöde från rådata till biologiska slutsatser. En av de stora utmaningarna i analys av mikromatriser är att kunna särskilja bruset från värdefull biologisk information. Att studera träd som växer utomhus är komplext eftersom de interagerar med omgivningen i mycket större utsträckning än vad som är fallet i växthusets kontrollerade miljö. Det här arbetet visar att det är möjligt, med hjälp av avancerad statistik och god försöksplanering, att följa och jämföra genuttrycket i blad från aspar utomhus under flera år för att dra värdefulla slutsatser om geners reglering. Den lagrade biologiska informationen i UPSC-BASE är avsedd att vara en värdefull tillgång för växtfältet i stort. I databasen finns nästan hundra olika experiment som innefattar alltifrån unga blad till ved, insektsangrepp, kyla och torka samt studier av genmodifierade växter. Informationen kan användas både för jämförande studier inom olika aspförsök, men också för att jämföra med andra växter. För att illustrera möjligheterna, studerades och grupperades gener i blad baserat på hur de uppträder över alla dessa experiment. Dessa grupperingar användes sedan för att definiera gener som är viktiga i bladutvecklingen. Sammanfattningsvis ger arbetet som presenteras i denna avhandling tillgång till verktyg och kunskap för storskaliga studier av genuttryck och den lagrade informationen har bevisats vara en värdefull tillgång för mer ingående studier av geners reglering.
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| 16. |
- Svensson, Daniel, et al.
(författare)
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A whole-genome sequenced control population in northern Sweden reveals subregional genetic differences
- 2020
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Ingår i: PLOS ONE. - : Public Library Science. - 1932-6203. ; 15:9
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Tidskriftsartikel (refereegranskat)abstract
- The number of national reference populations that are whole-genome sequenced are rapidly increasing. Partly driving this development is the fact that genetic disease studies benefit from knowing the genetic variation typical for the geographical area of interest. A whole-genome sequenced Swedish national reference population (n = 1000) has been recently published but with few samples from northern Sweden. In the present study we have whole-genome sequenced a control population (n = 300) (ACpop) from Västerbotten County, a sparsely populated region in northern Sweden previously shown to be genetically different from southern Sweden. The aggregated variant frequencies within ACpop are publicly available (DOI 10.17044/NBIS/G000005) to function as a basic resource in clinical genetics and for genetic studies. Our analysis of ACpop, representing approximately 0.11% of the population in Västerbotten, indicates the presence of a genetic substructure within the county. Furthermore, a demographic analysis showed that the population from which samples were drawn was to a large extent geographically stationary, a finding that was corroborated in the genetic analysis down to the level of municipalities. Including ACpop in the reference population when imputing unknown variants in a Västerbotten cohort resulted in a strong increase in the number of high-confidence imputed variants (up to 81% for variants with minor allele frequency < 5%). ACpop was initially designed for cancer disease studies, but the genetic structure within the cohort will be of general interest for all genetic disease studies in northern Sweden.
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| 17. |
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| 18. |
- Tuiskunen-Bäck, Anne, et al.
(författare)
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Clinical and genomic characterisation of a fatal Puumala orthohantavirus case with low levels of neutralising antibodies
- 2022
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Ingår i: Infectious Diseases. - : Informa UK Limited. - 2374-4235 .- 2374-4243. ; 54:10, s. 766-772
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Orthohantaviruses are rodent-borne emerging viruses that cause haemorrhagic fever with renal syndrome (HFRS) in Eurasia and hantavirus pulmonary syndrome in America. Transmission between humans have been reported and the case-fatality rate ranges from 0.4% to 40% depending on virus strain. There is no specific and efficient treatment for patients with severe HFRS. Here, we characterised a fatal case of HFRS and sequenced the causing Puumala orthohantavirus (PUUV).METHODS: PUUV RNA and virus specific neutralising antibodies were quantified in plasma samples from the fatal case and other patients with non-fatal PUUV infection. To investigate if the causing PUUV strain was different from previously known strains, Sanger sequencing was performed directly from the patient's plasma. Biopsies obtained from autopsy were stained for immunohistochemistry.RESULTS: The patient had approximately tenfold lower levels of PUUV neutralising antibodies and twice higher viral load than was normally seen for patients with less severe PUUV infection. We could demonstrate unique mutations in the S and M segments of the virus that could have had an impact on the severity of infection. Due to the severe course of infection, the patient was treated with the bradykinin receptor inhibitor icatibant to reduce bradykinin-mediated vessel permeability and maintain vascular circulation.CONCLUSIONS: Our data suggest that bradykinin receptor inhibitor may not be highly efficient to treat patients that are at an advanced stage of HFRS. Low neutralising antibodies and high viral load at admission to the hospital were associated with the fatal outcome and may be useful for future predictions of disease outcome.
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| 19. |
- Vallesi, Adriana, et al.
(författare)
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A New Species of the gamma-Proteobacterium Francisella, F. adeliensis Sp. Nov., Endocytobiont in an Antarctic Marine Ciliate and Potential Evolutionary Forerunner of Pathogenic Species
- 2019
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Ingår i: Microbial Ecology. - : Springer. - 0095-3628 .- 1432-184X. ; 77:3, s. 587-596
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Tidskriftsartikel (refereegranskat)abstract
- The study of the draft genome of an Antarctic marine ciliate, Euplotes petzi, revealed foreign sequences of bacterial origin belonging to the gamma-proteobacterium Francisella that includes pathogenic and environmental species. TEM and FISH analyses confirmed the presence of a Francisella endocytobiont in E. petzi. This endocytobiont was isolated and found to be a new species, named F. adeliensis sp. nov.. F. adeliensis grows well at wide ranges of temperature, salinity, and carbon dioxide concentrations implying that it may colonize new organisms living in deeply diversified habitats. The F. adeliensis genome includes the igl and pdp gene sets (pdpC and pdpE excepted) of the Francisella pathogenicity island needed for intracellular growth. Consistently with an F. adeliensis ancient symbiotic lifestyle, it also contains a single insertion-sequence element. Instead, it lacks genes for the biosynthesis of essential amino acids such as cysteine, lysine, methionine, and tyrosine. In a genome-based phylogenetic tree, F. adeliensis forms a new early branching clade, basal to the evolution of pathogenic species. The correlations of this clade with the other clades raise doubts about a genuine free-living nature of the environmental Francisella species isolated from natural and man-made environments, and suggest to look at F. adeliensis asa pioneer in the Francisella colonization of eukaryotic organisms.
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| 20. |
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