The evolution of hard tick-borne relapsing fever borreliae is correlated with vector species rather than geographical distance

Abstract Background Relapsing fever (RF) borreliae are arthropod-borne spirochetes and some of them cause human diseases, which are characterized by relapsing or recurring episodes of fever. Recently, it has been classified into two groups: soft tick-borne RF (STRF) borreliae and hard tick-borne RF (HTRF) borreliae. STRF borreliae include classical RF agents and HTRF borreliae, the latter of which include B. miyamotoi, a human pathogen recently identified in Eurasia and North America. Results In this study, we determined the genome sequences of 16 HTRF borreliae strains: 15 B. miyamotoi strains (9 from Hokkaido Island, Japan, 3 from Honshu Island, Japan, and 3 from Mongolia) and a Borrelia sp. tHM16w. Chromosomal gene synteny was highly conserved among the HTRF strains sequenced in this study, even though they were isolated from different geographic regions and different tick species. Phylogenetic analysis based on core gene sequences revealed that HTRF and STRF borreliae are clearly distinguishable, with each forming a monophyletic group in the RF borreliae lineage. Moreover, the evolutionary relationships of RF borreliae are consistent with the biological and ecological features of each RF borreliae sublineage and can explain the unique characteristics of Borrelia anserina. In addition, the pairwise genetic distances between HTRF borreliae strains were well correlated with those of vector species rather than with the geographical distances between strain isolation sites. This result suggests that the genetic diversification of HTRF borreliae is attributed to the speciation of vector ticks and that this relationship might be required for efficient transmission of HTRF borreliae within vector ticks. Conclusions The results of the present study, together with those from previous investigations, support the hypothesis that the common ancestor of borreliae was transmitted by hard-bodied ticks and that only STRF borreliae switched to using soft-bodied ticks as a vector, which was followed by the emergence of Borrelia recurrentis, lice-borne RF borreliae. Our study clarifies the phylogenetic relationships between RF borreliae, and the data obtained will contribute to a better understanding of the evolutionary history of RF borreliae.

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Biogeography and Independent Diversification in the Protist Symbiont Community of Heterotermes tenuis

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.640625 ◽

2021 ◽

Vol 9 ◽

Author(s):

Francesca De Martini ◽

Nicole L. Coots ◽

Daniel E. Jasso-Selles ◽

Jordyn Shevat ◽

Alison Ravenscraft ◽

...

Keyword(s):

Regional Differences ◽

Amplicon Sequencing ◽

Genetic Distances ◽

Species Level ◽

Mantel Tests ◽

Geographical Distances ◽

Host Phylogeny ◽

Single Cell Isolation ◽

Host Genetic ◽

Protist Species

The eukaryotic microbiome of “lower” termites is highly stable and host-specific. This is due to the mutually obligate nature of the symbiosis and the direct inheritance of protists by proctodeal trophallaxis. However, vertical transmission is occasionally imperfect, resulting in daughter colonies that lack one or more of the expected protist species. This phenomenon could conceivably lead to regional differences in protist community composition within a host species. Here, we have characterized the protist symbiont community of Heterotermes tenuis (Hagen) (Blattodea: Rhinotermitidae) from samples spanning South and Central America. Using light microscopy, single cell isolation, and amplicon sequencing, we report eight species-level protist phylotypes belonging to four genera in the phylum Parabasalia. The diversity and distribution of each phylotype’s 18S rRNA amplicon sequence variants (ASVs) mostly did not correlate with geographical or host genetic distances according to Mantel tests, consistent with the lack of correlation we observed between host genetic and geographical distances. However, the ASV distances of Holomastigotoides Ht3 were significantly correlated with geography while those of Holomastigotoides Ht1 were significantly correlated with host phylogeny. These results suggest mechanisms by which termite-associated protist species may diversify independently of each other and of their hosts, shedding light on the coevolutionary dynamics of this important symbiosis.

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Генетический полиморфизм редких и малораспространенных аборигенных донских генотипов L

Magarach. Vinogradstvo i Vinodelie ◽

10.35547/im.2019.21.3.002 ◽

2019 ◽

pp. 191-197 ◽

Cited By ~ 1

Author(s):

Elena Ilnitskaya ◽

Lyudmila Naumova ◽

Valentina Ganich ◽

Sergey Tokmakov ◽

Marina Makarkina

Keyword(s):

Vitis Vinifera ◽

Genetic Similarity ◽

Genetic Distances ◽

The Other ◽

Vitis Vinifera L ◽

Separate Branch ◽

History Of ◽

The Difference ◽

Dna Profiles ◽

Basic Minimum

История виноградарства на Дону насчитывает несколько веков, местные сорта винограда многообразны и специфичны. Микросателлитные маркеры широко используются для генотипирования сортов и подвоев винограда, при изучении происхождения сортов и анализе их родословной. Целью исследования было изучение выборки редких и малораспространенных автохтонных донских сортов и сравнение их с другими аборигенными донскими генотипами на основе данных ДНК-анализа. В исследования включены 23 стародавних донских сорта. Генотипирование проводили методом микросателлитного профилирования. В исследовании использовали микросателлитные маркеры (SSR), рекомендованные в качестве основного минимального набора для ДНК-паспортизации сортов вида Vitis vinifera L.: VVMD5, VVMD7, VVMD27, VVS2, VrZAG62 и VrZAG79. По результатам проведенного анализа все изученные образцы показали сорт-специфическую комбинацию аллелей в идентифицированных ДНК-профилях. Количество выявленных аллелей составило в среднем 8 аллелей/локус. Наибольший полиморфизм в исследовании этой группы донских сортов был обнаружен в локусе VVMD5: идентифицировано 10 аллелей на локус, наименьшее - в локусе VrZAG62: 6 аллелей/локус. Основываясь на данных SSR-анализа, степень генетического сходства сортов оценивали с использованием метода UPGMA. Кластерный анализ матрицы генетических дистанций, созданный на основе выявленных значений аллелей в шести микросателлитных локусах исследуемых сортов, определил несколько групп генотипов. Сорт Красностоп золотовский выделился в отдельную ветвь, что указывает на различия между этим генотипом и другими сортами исследуемой выборки. Наивысший уровень генетического сходства наблюдался между следующими парами сортов: Крестовский и Бургундский, Шилохвостый и Мушкетный, Кумшацкий черный и Ефремовский.The history of viticulture on the Don goes back several centuries. Local grapevine varieties are diverse and peculiar. Microsatellite markers are widely used in genotyping grapevine cultivars and rootstocks, in grapevine origin and breeding background analysis. Our study aimed to examine samples of rare and less common autochthonous Don varieties, and compare them with the other aboriginal Don genotypes using DNA data. The study involved 23 traditional Don varieties. The genotyping was done by microsatellite profiling. The study used microsatellite (SSR) markers recommended as the basic minimum set for DNA-certification of the genotypes of Vitis vinifera L.: VVMD5, VVMD7, VVMD27, VVS2, VrZAG62 and VrZAG79. Based on the findings, all the studied samples demonstrated variety-specific combination of alleles in the identified DNA profiles. The number of detected alleles on average was 8 alleles/locus. The greatest polymorphism in the studied group of Don varieties was detected in VVMD5 locus: 10 alleles per locus were identified, the smallest in VrZAG62 locus: 6 alleles/locus. UPGMA method was used to assess the extent of genetic similarity of the varieties based on SSR-genotyping data. Based on determined allele values of the studied varieties, cluster analysis of the genetic distances matrix determined several groups of genotypes. ‘Krasnostop zolotovskiy’ variety stood out as a separate branch, which indicates the difference between this genotype and the other varieties of the studied sampling. The highest level of genetic similarity was observed between the following pairs of varieties: ‘Krestovskiy’ and ‘Burgundskiy’, ‘Shilohvostyi’ and ‘Mushketnyi’, ‘Kumshatskiy chornyi’ and ‘Efremovskiy’.

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Borreliae Part 2: Borrelia Relapsing Fever Group and Unclassified Borrelia

Biology ◽

10.3390/biology10111117 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1117

Author(s):

Giusto Trevisan ◽

Marina Cinco ◽

Sara Trevisini ◽

Nicola di Meo ◽

Maurizio Ruscio ◽

...

Keyword(s):

Geographical Distribution ◽

New World ◽

Common Ancestor ◽

Etiological Agent ◽

Hard Tick ◽

Soft Tick ◽

Relapsing Fever ◽

Old World ◽

Pediculus Humanus ◽

Candidate Species

Borreliae of the relapsing fever group (RFG) are heterogenous and can be divided mainly into three groups according to vectors, namely the soft-tick-borne relapsing fever (STBRF) Borreliae, the hard-tick-borne relapsing fever (HTBRF) Borreliae, the louse-borne relapsing fever (LBRF) Borreliae, and the avian relapsing fever ones. With respect to the geographical distribution, the STBRF Borreliae are further subdivided into Old World and New World strains. Except for the Avian relapsing fever group Borreliae, which cause avian spirochetosis, all the others share infectivity in humans. They are indeed the etiological agent of both endemic and epidemic forms of relapsing fever, causing high spirochaetemia and fever. Vectors are primarily soft ticks of Ornithodoros spp. in the STBRF group; hard ticks, notably Ixodes sp., Amblyomma sp., Dermacentor sp., and Rhipicephalus sp., in the HTBRF group; and the louse pediculus humanus humanus in the TBRF one. A recent hypothesis was supported for a common ancestor of RFG Borreliae, transmitted at the beginning by hard-body ticks. Accordingly, STBRF Borreliae switched to use soft-bodied ticks as a vector, which was followed by the use of lice by Borrelia recurrentis. There are also new candidate species of Borreliae, at present unclassified, which are also described in this review.

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A novel relapsing fever Borrelia sp. infects the salivary glands of the molted hard tick, Amblyomma geoemydae

Ticks and Tick-borne Diseases ◽

10.1016/j.ttbdis.2012.06.003 ◽

2012 ◽

Vol 3 (4) ◽

pp. 259-261 ◽

Cited By ~ 19

Author(s):

Ai Takano ◽

Chieko Sugimori ◽

Hiromi Fujita ◽

Teruki Kadosaka ◽

Kyle R. Taylor ◽

...

Keyword(s):

Salivary Glands ◽

Hard Tick ◽

Relapsing Fever

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Blood Smears Have Poor Sensitivity for ConfirmingBorrelia miyamotoiDisease

Journal of Clinical Microbiology ◽

10.1128/jcm.01468-18 ◽

2019 ◽

Vol 57 (3) ◽

Cited By ~ 1

Author(s):

Sam R. Telford ◽

Heidi K. Goethert ◽

Philip J. Molloy ◽

Victor Berardi

Keyword(s):

Lyme Disease ◽

Morphological Evidence ◽

Hard Tick ◽

Borrelia Miyamotoi ◽

Relapsing Fever ◽

Main Mode ◽

Blood Samples ◽

Content Type ◽

Blood Smears ◽

Thick Smear

ABSTRACTBorrelia miyamotoidisease (BMD) is a newly recognized borreliosis that is cotransmitted by ticks wherever Lyme disease is zoonotic. UnlikeBorrelia burgdorferisensu lato, the agent of Lyme disease,B. miyamotoiis closely related to relapsing fever spirochetes, such asBorrelia hermsii. Some authors have suggested that the disease caused byB. miyamotoishould be considered a hard-tick-transmitted relapsing fever, and thus, the main mode of confirming a diagnosis for that infection, microscopy to analyze a blood smear, may have clinical utility. To determine whether blood smears may detectB. miyamotoiin the blood of acute BMD patients, we made standard malariological thick smears from anticoagulated blood samples that were previously determined to contain this agent (by PCR) and analyzed them for morphological evidence of spirochetes. Spirochetes were not detected in the blood smears from 20 PCR positive patient blood samples after examination of 100 thick smear fields and only 2 of 20 demonstrated spirochetes when the examination was extended to 300 thick smear fields. Inoculation of severe combined immunodeficient (SCID) mice yielded isolates from 5 of 5 samples, but 0 of 3 BALB/c mice became infected. We conclude that in strong contrast to the diagnosis of typical relapsing fever, microscopy of blood smears is not sensitive enough for confirming a diagnosis of BMD but that SCID mouse inoculation could be a useful complement to PCR.

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‘Candidatus Borrelia texasensis’, from the American dog tick Dermacentor variabilis

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijs.0.02864-0 ◽

2005 ◽

Vol 55 (2) ◽

pp. 685-693 ◽

Cited By ~ 26

Author(s):

Tao Lin ◽

Lihui Gao ◽

Andreas Seyfang ◽

James H. Oliver

Keyword(s):

Dna Hybridization ◽

Rapd Analysis ◽

Rflp Analysis ◽

Dermacentor Variabilis ◽

Genetic Distances ◽

Rrna Gene ◽

Relapsing Fever ◽

Tick Feeding ◽

Culture Collections ◽

Banding Patterns

TXW-1, a Borrelia strain isolated in March 1998 from an adult male Dermacentor variabilis tick feeding on a coyote from Webb county, Texas, USA, was characterized by using randomly amplified polymorphic DNA (RAPD) analysis, RFLP and sequence analysis of flaB and rrs (16S rRNA gene), DNA–DNA hybridization analysis, SDS-PAGE and Western blotting with mAbs. It shows different banding patterns in RFLP analysis of flaB and forms distinct branches in phylogenetic analysis derived from flaB and rrs genes. It differs from other borreliae based on the banding patterns obtained by RAPD analysis. This strain contains a small, 38-kDa endoflagellar protein. DNA–DNA hybridization experiments revealed that the levels of DNA reassociation between TXW-1 and previously described relapsing fever borreliae were 38·64 % (Borrelia turicatae), 38·40 % (Borrelia parkeri), 7·39 % (Borrelia hermsii) and 18·30 % (Borrelia coriaceae). However, the level of DNA relatedness between B. parkeri and B. turicatae was 78·78 %. Sequence analyses of flaB and rrs genes indicate that the similarities of nucleotide sequences among TXW-1 and B. turicatae or B. parkeri are less than that between B. turicatae and B. parkeri, and that the genetic distances among TXW-1 and B. turicatae or B. parkeri are greater than that between B. turicatae and B. parkeri. TXW-1 lacks an ospC gene. Electron microscope observations showed that this spirochaete had different morphological structures compared to previously described relapsing fever borreliae. All the results obtained from the above-mentioned analyses indicate that TXW-1 is different from other described Borrelia species and that it represents a novel species of Borrelia. We have been unable to revive frozen cultures and so can not meet the requirements of the Bacteriological Code to deposit viable type material at two different culture collections. Therefore we use the Candidatus designation; based on these results, the species ‘Candidatus Borrelia texasensis' is proposed.

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A transcriptome-based phylogenetic study of hard ticks (Ixodidae)

Scientific Reports ◽

10.1038/s41598-019-49641-9 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 6

Author(s):

N. Pierre Charrier ◽

Axelle Hermouet ◽

Caroline Hervet ◽

Albert Agoulon ◽

Stephen C. Barker ◽

...

Keyword(s):

Evolutionary History ◽

Nuclear Genome ◽

Single Copy ◽

Phylogenetic Study ◽

Data Sets ◽

Hard Tick ◽

Rna Seq ◽

Hard Ticks ◽

History Of ◽

Mitochondrial Sequences

Abstract Hard ticks are widely distributed across temperate regions, show strong variation in host associations, and are potential vectors of a diversity of medically important zoonoses, such as Lyme disease. To address unresolved issues with respect to the evolutionary relationships among certain species or genera, we produced novel RNA-Seq data sets for nine different Ixodes species. We combined this new data with 18 data sets obtained from public databases, both for Ixodes and non-Ixodes hard tick species, using soft ticks as an outgroup. We assembled transcriptomes (for 27 species in total), predicted coding sequences and identified single copy orthologues (SCO). Using Maximum-likelihood and Bayesian frameworks, we reconstructed a hard tick phylogeny for the nuclear genome. We also obtained a mitochondrial DNA-based phylogeny using published genome sequences and mitochondrial sequences derived from the new transcriptomes. Our results confirm previous studies showing that the Ixodes genus is monophyletic and clarify the relationships among Ixodes sub-genera. This work provides a baseline for studying the evolutionary history of ticks: we indeed found an unexpected acceleration of substitutions for mitochondrial sequences of Prostriata, and for nuclear and mitochondrial genes of two species of Rhipicephalus, which we relate with patterns of genome architecture and changes of life-cycle, respectively.

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Molecular diversity of small balsam populations in relation to site characteristics

Open Life Sciences ◽

10.2478/s11535-013-0228-3 ◽

2013 ◽

Vol 8 (10) ◽

pp. 1048-1061 ◽

Cited By ~ 3

Author(s):

Eugenija Kupcinskiene ◽

Lina Zybartaite ◽

Rasa Janulioniene ◽

Judita Zukauskiene ◽

Algimantas Paulauskas

Keyword(s):

Molecular Diversity ◽

Genetic Distances ◽

Randomly Amplified Polymorphic Dna ◽

Multiple Introductions ◽

Habitat Features ◽

Site Characteristics ◽

Impatiens Parviflora ◽

Geographical Distances ◽

Favorable Conditions ◽

Simple Sequence

AbstractClimatic shifts within recent decades created favorable conditions for invasive species flourishing in more Northern parts of Europe. Our study was aimed at evaluation of genetic variability and habitat features of Impatiens parviflora populations growing in Lithuania. Twenty one populations were selected and analysed using simple sequence repeat (SSR) and randomly amplified polymorphic DNA (RAPD) assays. Evaluated by SSRs, 315 individuals were all monomorphic and homozygous at 4 loci and heterozygous at 1 locus. RAPD analyses revealed that the percentage of polymorphic DNA loci (% P) per population ranged from 7 to 39% and genetic differentiation between populations was ΦPT=0.790 (P<0.01). Genetic distances among populations (0.135–0.426) correlated significantly with geographical distances (r=0.183; P<0.008). Populations in overmoistured soil contained higher % P (28.3) when compared to drier soil (18.7; P<0.05). All recorded populations were close to roads; their % P did not depend on proximity to buildings, light intensity or population size. Our RAPD analyses indicate multiple introductions of this species in Lithuania. Analyses of I. parviflora at SSR and RAPD loci show that the invasion process is reflected in genetic structure.

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