scholarly journals Sequence of a Coxiella endosymbiont of the tick Amblyomma nuttalli suggests a pattern of convergent genome reduction in the Coxiella genus

2020 ◽  
Author(s):  
Tiago Nardi ◽  
Emanuela Olivieri ◽  
Edward Kariuki ◽  
Davide Sassera ◽  
Michele Castelli
Keyword(s):  
Coxiella Burnetii ◽  
Phylogenetic Analyses ◽  
Genome Reduction ◽  
Metabolic Profiles ◽  
The Novel ◽  
Bacterial Symbionts ◽  
Human Pathogen ◽  
Host Genus ◽  
Supportive Role ◽  
Genus One

Abstract Ticks require bacterial symbionts for the provision of necessary compounds that are absent in their hematophagous diet. Such symbionts are frequently vertically transmitted and, most commonly, belong to the Coxiella genus, which also includes the human pathogen Coxiella burnetii. This genus can be divided in four main clades, presenting partial but incomplete co-cladogenesis with the tick hosts. Here we report the genome sequence of a novel Coxiella, endosymbiont of the African tick Amblyomma nuttalli, and the ensuing comparative analyses. Its size (~1 Mb) is intermediate between symbionts of Rhipicephalus species and other Amblyomma species. Phylogenetic analyses show that the novel sequence is the first genome of the B clade, the only one for which no genomes were previously available. Accordingly, it allows to draw an enhanced scenario of the evolution of the genus, one of parallel genome reduction of different endosymbiont lineages, which are now at different stages of reduction from a more versatile ancestor. Gene content comparison allows to infer that the ancestor could be reminiscent of Coxiella burnetii. Interestingly, the convergent loss of mismatch repair could have been a major driver of such reductive evolution. Predicted metabolic profiles are rather homogenous among Coxiella endosymbionts, in particular vitamin biosynthesis, consistently with a host-supportive role. Concurrently, similarities among Coxiella endosymbionts according to host genus and despite phylogenetic unrelatedness hint at possible host-dependent effects.

scholarly journals Sequence of a Coxiella endosymbiont of the tick Amblyomma nuttalli suggests a pattern of convergent genome reduction in the Coxiella genus

2020 ◽  
Author(s):  
Tiago Nardi ◽  
Emanuela Olivieri ◽  
Edward Kariuki ◽  
Davide Sassera ◽  
Michele Castelli
Keyword(s):  
Genome Sequence ◽  
Coxiella Burnetii ◽  
Current Knowledge ◽  
Phylogenetic Analyses ◽  
Genome Reduction ◽  
Ancestral State ◽  
Host Genus ◽  
Functional Capabilities ◽  
Supportive Role ◽  
Selective Retention

AbstractTicks require bacterial symbionts for the provision of necessary compounds that are absent in their hematophagous diet. Such symbionts are frequently vertically transmitted and, most commonly, belong to the Coxiella genus, which also includes the human pathogen Coxiella burnetii. This genus can be divided in four main clades, presenting partial but incomplete co-cladogenesis with the tick hosts. Here we report the genome sequence of a novel Coxiella, endosymbiont of the African tick Amblyomma nuttalli, and the ensuing comparative analyses. Its size (∼1 Mb) is intermediate between symbionts of Rhipicephalus species and other Amblyomma species. Phylogenetic analyses show that the novel sequence is the first genome of the B clade, the only one for which no genomes were previously available. Accordingly, it allows to draw an enhanced scenario of the evolution of the genus, one of parallel genome reduction of different endosymbiont lineages, which are now at different stages of reduction from a more versatile ancestor. Gene content comparison allows to infer that the ancestor could be reminiscent of Coxiella burnetii. Interestingly, the convergent loss of mismatch repair could have been a major driver of such reductive evolution. Predicted metabolic profiles are rather homogenous among Coxiella endosymbionts, in particular vitamin biosynthesis, consistently with a host-supportive role. Concurrently, similarities among Coxiella endosymbionts according to host genus and despite phylogenetic unrelatedness hint at possible host-dependent effects.Significance statementThe genus Coxiella includes the pathogen Coxiella burnetii and widespread nutritional mutualists in ticks. Current knowledge on their evolution is hampered by the limited genomic resources available.Here we provide the first genome sequence of a Coxiella endosymbiont of clade B, the only clade for which none was available.These data allow to infer an evolutionary scenario of parallel genome reduction among Coxiella endosymbionts, with similar constraints, leading to selective retention of biosynthetic pathways beneficial for the host. The combined predicted functional capabilities of the symbionts appear to be a subset of those of C. burnetii. Accordingly, this pathogen could be closer to an ancestral state of the endosymbionts, rather than being derived from an endosymbiotic ancestor, as previously hypothesized.

scholarly journals A Freeloader?: The Highly Eroded Yet large Genome of the Serratia symbiotica symbiont of Cinara strobi

2018 ◽  
Author(s):  
Alejandro Manzano-Marín ◽  
Armelle Coeur d’acier ◽  
Anne-Laure Clamens ◽  
Céline Orvain ◽  
Corinne Cruaud ◽  
...  
Keyword(s):  
Amplicon Sequencing ◽  
Genome Reduction ◽  
The Novel ◽  
Bacterial Symbionts ◽  
Buchnera Aphidicola ◽  
Essential Nutrients ◽  
Apparent Lack ◽  
Obligate Symbiont ◽  
Bacterial Endosymbionts ◽  
Serratia Symbiotica

ABSTRACTGenome reduction is pervasive among maternally-inherited bacterial endosymbionts. This genome reduction can eventually lead to serious deterioration of essential metabolic pathways, thus rendering an obligate endosymbiont unable to provide essential nutrients to its host. This loss of essential pathways can lead to either symbiont complementation (sharing of the nutrient production with a novel co-obligate symbiont) or symbiont replacement (complete takeover of nutrient production by the novel symbiont). However, the process by which these two evolutionary events happen remains somewhat enigmatic by the lack of examples of intermediate stages of this process. Cinara aphids (Hemiptera: Aphididae) typically harbour two obligate bacterial symbionts: Buchnera and Serratia symbiotica. However, the latter has been replaced by different bacterial taxa in specific lineages, and thus species within this aphid lineage could provide important clues into the process of symbiont replacement. In the present study, using 16S rRNA high-throughput amplicon sequencing, we determined that the aphid Cinara strobi harbours not two, but three fixed bacterial symbionts: Buchnera aphidicola, a Sodalis sp., and S. symbiotica. Through genome assembly and genome-based metabolic inference, we have found that only the first two symbionts (Buchnera and Sodalis) actually contribute to the hosts’ supply of essential nutrients while S. symbiotica has become unable to contribute towards this task. We found that S. symbiotica has a rather large and highly eroded genome which codes only for a few proteins and displays extensive pseudogenisation. Thus, we propose an ongoing symbiont replacement within C. strobi, in which a once ‘‘competent” S. symbiotica does no longer contribute towards the beneficial association. These results suggest that in dual symbiotic systems, when a substitute co-symbiont is available, genome deterioration can precede genome reduction and a symbiont can be maintained despite the apparent lack of benefit to its host.

scholarly journals Cryptosporidium myocastoris n. sp. (Apicomplexa: Cryptosporidiidae), the Species Adapted to the Nutria (Myocastor coypus)

2021 ◽  
Vol 9 (4) ◽  
pp. 813
Author(s):  
Jana Ježková ◽  
Zlata Limpouchová ◽  
Jitka Prediger ◽  
Nikola Holubová ◽  
Bohumil Sak ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Clinical Signs ◽  
Prepatent Period ◽  
Cryptosporidium Species ◽  
The Novel ◽  
Myocastor Coypus ◽  
The Czech Republic ◽  
Molecular Analyses ◽  
Cryptosporidium Spp ◽  
Faecal Samples

Cryptosporidium spp., common parasites of vertebrates, remain poorly studied in wildlife. This study describes the novel Cryptosporidium species adapted to nutrias (Myocastor coypus). A total of 150 faecal samples of feral nutria were collected from locations in the Czech Republic and Slovakia and examined for Cryptosporidium spp. oocysts and specific DNA at the SSU, actin, HSP70, and gp60 loci. Molecular analyses revealed the presence of C. parvum (n = 1), C. ubiquitum subtype family XIId (n = 5) and Cryptosporidium myocastoris n. sp. XXIIa (n = 2), and XXIIb (n = 3). Only nutrias positive for C. myocastoris shed microscopically detectable oocysts, which measured 4.8–5.2 × 4.7–5.0 µm, and oocysts were infectious for experimentally infected nutrias with a prepatent period of 5–6 days, although not for mice, gerbils, or chickens. The infection was localised in jejunum and ileum without observable macroscopic changes. The microvilli adjacent to attached stages responded by elongating. Clinical signs were not observed in naturally or experimentally infected nutrias. Phylogenetic analyses at SSU, actin, and HSP70 loci demonstrated that C. myocastoris n. sp. is distinct from other valid Cryptosporidium species.

scholarly journals Rubritalea halochordaticola sp. nov., a carotenoid-producing verrucomicrobial species isolated from a marine chordate

2011 ◽  
Vol 61 (7) ◽  
pp. 1515-1520 ◽  
Author(s):  
Jaewoo Yoon ◽  
Satoru Matsuda ◽  
Kyoko Adachi ◽  
Hiroaki Kasai ◽  
Akira Yokota
Keyword(s):  
Dna Hybridization ◽  
Sequence Similarity ◽  
Phylogenetic Analyses ◽  
Diaminopimelic Acid ◽  
Rrna Gene ◽  
The Novel ◽  
16S Rrna Gene Sequences ◽  
Sea Squirt ◽  
Cell Biomass ◽  
Taxonomic Approach

A Gram-negative-staining, obligately aerobic, non-motile, rod-shaped and chemoheterotrophic bacterium, designated strain MN1-1006T, was isolated from an ascidian (sea squirt) sample, and was studied using a polyphasic taxonomic approach. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the new isolate shared approximately 93–99% sequence similarity with recognized species of the genus Rubritalea within the phylum ‘Verrucomicrobia’. DNA–DNA hybridization values between strain MN1-1006T and Rubritalea squalenifaciens HOact23T and Rubritalea sabuli YM29-052T were 57% and 14.5%, respectively. Strain MN1-1006T produced carotenoid compounds that rendered the cell biomass a reddish pink colour. The strain also contained squalene. The cell-wall peptidoglycan of the novel strain contained muramic acid and meso-diaminopimelic acid. The DNA G+C content of strain MN1-1006T was 51.4 mol%. The major cellular fatty acids were iso-C14:0, iso-C16:0 and anteiso-C15:0. The major isoprenoid quinone was MK-9. On the basis of these data, it was concluded that strain MN1-1006T represents a novel species of the genus Rubritalea, for which the name Rubritalea halochordaticola sp. nov. is proposed. The type strain is MN1-1006T ( = KCTC 23186T = NBRC 107102T).

scholarly journals Diversity and Phylogenetic Analyses of Bacterial Symbionts in Three Whitefly Species from Southeast Europe

Insects ◽  
2017 ◽  
Vol 8 (4) ◽  
pp. 113 ◽  
Author(s):  
Marisa Skaljac ◽  
Surapathrudu Kanakala ◽  
Katja Zanic ◽  
Jasna Puizina ◽  
Ivana Lepen Pleic ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Bacterial Symbionts ◽  
Southeast Europe

Methanobacterium lacus sp. nov., isolated from the profundal sediment of a freshwater meromictic lake

2012 ◽  
Vol 62 (Pt_7) ◽  
pp. 1625-1629 ◽  
Author(s):  
Guillaume Borrel ◽  
Keith Joblin ◽  
Annie Guedon ◽  
Jonathan Colombet ◽  
Vincent Tardy ◽  
...  
Keyword(s):  
Rumen Fluid ◽  
Sequence Similarity ◽  
Phylogenetic Analyses ◽  
Meromictic Lake ◽  
Rrna Gene ◽  
The Novel ◽  
Content Type ◽  
Link Type ◽  
Gram Staining ◽  
Lake Pavin

An autotrophic, hydrogenotrophic methanogen, designated strain 17A1T, was isolated from the profundal sediment of the meromictic Lake Pavin, France. The cells of the novel strain, which were non-motile, Gram-staining-negative rods that measured 2–15 µm in length and 0.2–0.4 µm in width, grew as filaments. Strain 17A1T grew in a mineral medium and its growth was stimulated by the addition of yeast extract, vitamins, acetate or rumen fluid. Penicillin, vancomycin and kanamycin reduced growth but did not completely inhibit it. Growth occurred at 14–41 °C (optimum 30 °C), at pH 5.0–8.5 (optimum pH 6.5) and with 0–0.4 M NaCl (optimum 0.1 M). The novel strain utilized H2/CO2 and methanol/H2 as substrates but not formate, acetate, methylamine/H2, isobutanol or 2-propanol. Its genomic DNA G+C content was 37.0 mol%. In phylogenetic analyses based on 16S rRNA gene sequences, strain 17A1T appeared to be a member of the genus Methanobacterium , with Methanobacterium beijingense 8-2T (96.3 % sequence similarity) identified as the most closely related established species. Based on phenotypic and phylogenetic data, strain 17A1T represents a novel species of methanogen within the genus Methanobacterium , for which the name Methanobacterium lacus sp. nov. is proposed. The type strain is 17A1T ( = DSM 24406T = JCM 17760T).

scholarly journals Vitellibacter echinoideorum sp. nov., isolated from a sea urchin (Tripneustes gratilla)

2015 ◽  
Vol 65 (Pt_7) ◽  
pp. 2320-2325 ◽  
Author(s):  
Shih-Yao Lin ◽  
Asif Hameed ◽  
Cheng-Zhe Wen ◽  
You-Cheng Liu ◽  
Yi-Han Hsu ◽  
...  
Keyword(s):  
16S Rrna ◽  
Sea Urchins ◽  
Sequence Similarity ◽  
Phylogenetic Analyses ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
The Novel ◽  
Moderate Amount ◽  
Polar Lipid Profile

A Gram-stain-negative, aerobic, rod-shaped, yellow-pigment-producing bacterium (designated strain CC-CZW007T) was isolated from seafood samples (sea urchins) at Penghu Island in Taiwan. Strain CC-CZW007T grew optimally at pH 7.0 and 30 °C in the presence of 3 % (w/v) NaCl. The novel strain shared highest 16S rRNA gene sequence similarity to Vitellibacter vladivostokensis JCM 11732T (96.8 %), Vitellibacter soesokkakensis KCTC 32536T (96.4 %), Vitellibacter nionensis KCTC 32420T (95.8 %) and Vitellibacter aestuarii JCM 15496T (95.6 %) and lower sequence similarity to members of other genera. Phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by strain CC-CZW007T with respect to other species of the genus Vitellibacter. The major fatty acids were iso-C15 : 0 and iso-C17 : 0 3-OH. The polar lipid profile was composed of major amounts of phosphatidylethanolamine, unidentified lipids and aminolipids; a moderate amount of aminophospholipid was also detected. The DNA G+C content was 34.7 mol%. The predominant quinone system was menaquinone (MK-6). On the basis of polyphasic taxonomic evidence presented here, strain CC-CZW007T is proposed to represent a novel species within the genus Vitellibacter, for which the name Vitellibacter echinoideorum sp. nov. is proposed. The type strain is CC-CZW007T ( = BCRC 80886T = JCM 30378T).

Morphology and phylogenetic analyses reveal Montagnula puerensis sp. nov. (Didymosphaeriaceae, Pleosporales) from southwest China

Phytotaxa ◽  
2021 ◽  
Vol 514 (1) ◽  
pp. 1-25
Author(s):  
TIANYE DU ◽  
KEVIN D. HYDE ◽  
AUSANA MAPOOK ◽  
PETER E. MORTIMER ◽  
JIANCHU XU ◽  
...  
Keyword(s):  
Yunnan Province ◽  
Southwest China ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Morphological Characteristics ◽  
Location Information ◽  
Fruiting Bodies ◽  
Host Genus ◽  
Extant Species ◽  
Culture Characteristics

A dead woody sample of Acer sp. with fungal fruiting bodies was collected in Pu’er City of Yunnan Province. Multigene phylogenetic analyses of LSU, ITS, SSU, and tef1-α sequence data showed that our collection belongs to Montagnula and is well separated from all other extant species. Montagnula puerensis is compared with all extant species by morphological characteristics, culture characteristics, host, and location information and is the first report of Montagnula from the host genus Acer.

scholarly journals Investigations into a putative role for the novel BRASSIKIN pseudokinases in compatible pollen-stigma interactions in Arabidopsis thaliana

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Jennifer Doucet ◽  
Hyun Kyung Lee ◽  
Nethangi Udugama ◽  
Jianfeng Xu ◽  
Baoxiu Qi ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Stop Codon ◽  
Phylogenetic Analyses ◽  
Premature Stop Codon ◽  
The Novel ◽  
Specific Expression ◽  
Deletion Mutations ◽  
Brassicaceae Species ◽  
Compatible Pollen ◽  
Compatible Interactions

Abstract Background In the Brassicaceae, the early stages of compatible pollen-stigma interactions are tightly controlled with early checkpoints regulating pollen adhesion, hydration and germination, and pollen tube entry into the stigmatic surface. However, the early signalling events in the stigma which trigger these compatible interactions remain unknown. Results A set of stigma-expressed pseudokinase genes, termed BRASSIKINs (BKNs), were identified and found to be present in only core Brassicaceae genomes. In Arabidopsis thaliana Col-0, BKN1 displayed stigma-specific expression while the BKN2 gene was expressed in other tissues as well. CRISPR deletion mutations were generated for the two tandemly linked BKNs, and very mild hydration defects were observed for wild-type Col-0 pollen when placed on the bkn1/2 mutant stigmas. In further analyses, the predominant transcript for the stigma-specific BKN1 was found to have a premature stop codon in the Col-0 ecotype, but a survey of the 1001 Arabidopsis genomes uncovered three ecotypes that encoded a full-length BKN1 protein. Furthermore, phylogenetic analyses identified intact BKN1 orthologues in the closely related outcrossing Arabidopsis species, A. lyrata and A. halleri. Finally, the BKN pseudokinases were found to be plasma-membrane localized through the dual lipid modification of myristoylation and palmitoylation, and this localization would be consistent with a role in signaling complexes. Conclusion In this study, we have characterized the novel Brassicaceae-specific family of BKN pseudokinase genes, and examined the function of BKN1 and BKN2 in the context of pollen-stigma interactions in A. thaliana Col-0. Additionally, premature stop codons were identified in the predicted stigma specific BKN1 gene in a number of the 1001 A. thaliana ecotype genomes, and this was in contrast to the out-crossing Arabidopsis species which carried intact copies of BKN1. Thus, understanding the function of BKN1 in other Brassicaceae species will be a key direction for future studies.

scholarly journals Blastococcus jejuensis sp. nov., an actinomycete from beach sediment, and emended description of the genus Blastococcus Ahrens and Moll 1970

2006 ◽  
Vol 56 (10) ◽  
pp. 2391-2396 ◽  
Author(s):  
Soon Dong Lee
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Sequence Similarity ◽  
Phylogenetic Analyses ◽  
Rrna Gene ◽  
The Novel ◽  
Separate Species ◽  
Beach Sediment ◽  
Actinomycete Strain ◽  
Type Strains

A novel actinomycete, strain KST3-10T, was isolated from sand sediment of a beach in Jeju, Korea, and was subjected to polyphasic taxonomic characterization. The organism produced circular, smooth, translucent, apricot-coloured colonies comprising coccoid- or rod-shaped cells. Phylogenetic analyses based on 16S rRNA gene sequences showed that the organism belonged to the family Geodermatophilaceae and consistently formed a distinct sub-branch outside the radiation of the genus Blastococcus. The organism showed 16S rRNA gene sequence similarity values of 98.2 % with respect to Blastococcus aggregatus DSM 4725T and 98.1 % with respect to Blastococcus saxobsidens BC444T. The type strains of the two Blastococcus species shared 98.2 % sequence similarity with respect to each other, whereas the levels of sequence similarity between the novel organism and the type strains of the less closely related neighbours, Modestobacter multiseptatus and Geodermatophilus obscurus, were in the range 96.2–96.9 %. The physiological, biochemical and chemotaxonomic data revealed that the novel organism can be readily differentiated from members of the genus Blastococcus and that it merits separate species status. On the basis of the phenotypic and genotypic evidence, strain KST3-10T represents a novel species of the genus Blastococcus, for which the name Blastococcus jejuensis sp. nov. is proposed. The type strain is KST3-10T (=NRRL B-24440T=KCCM 42251T).

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