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Background Louse-borne trench fever caused by Bartonella quintana is a neglected public health concern, known to be transmitted from body louse feces via scratching. No viable B. quintana have ever been isolated from head lice before; therefore, their role as a vector is still poorly understood. Methods In Senegal, the implementation of a permanent local surveillance system in a point-of-care laboratory (POC) allows the monitoring of emerging diseases. Here we used culture as well as molecular and genomic approaches to document an outbreak of trench fever associated with head lice in the village of Ndiop. Head lice and blood samples were collected from febrile patients between November 2010 and April 2015. Genomes of 2 isolated strains of B. quintana were sequenced and analyzed. Results A total of 2289 blood samples were collected in the 2010–2015 period. From 2010–2013, B. quintana DNA was detected by polymerase chain reaction (PCR) in 0.25% (4/1580). In 2014, 228 blood samples were collected, along with 161 head lice from 5 individuals. B. quintana DNA was detected in 4.4% (10/228) of blood samples, and in lice specimens collected from febrile patients (61.7%, 50/81) and non-febrile patients (61.4%, 43/70). Two B. quintana strains were isolated from blood and head lice from 2 different patients. Genomic sequence analysis showed 99.98% overall similarity between both strains. Conclusions The presence of live B. quintana in head lice, and the genetic identity of strains from patients' blood and head lice during a localized outbreak in Senegal, supports the evidence of head lice vectorial capacity. [ABSTRACT FROM AUTHOR]

To date there are thirteen species validly assigned to the genus Anaerococcus. Most of the species in this genus are anaerobic and of human origin. Anaerococcus urinimassiliensis sp. nov., strain Marseille-P2143T is member of family Peptoniphilaceae, which was isolated from the urine of a 17-year-old boy affected by autoimmune hepatitis and membranoproliferative glomerulonephritis using the culturomic approach. In the current study, a taxono-genomics method was employed to describe this new species. The strain Marseille-P2143T was gram positive cocci with translucent colonies on blood agar. Its genome was 2,189,509 bp long with a 33.5 mol% G + C content and exhibited 98.48% 16S rRNA similarity with Anaerococcus provencensis strain 9,402,080. When Anaerococcus urinomassiliensis strain Marseill-P2143T is compared with closely related species, the values ranged from 71.23% with A. hydrogenalis strain DSM 7454T (NZ_ABXA01000052.1) to 90.64% with A. provencensis strain 9402080T (NZ_HG003688.1). This strain has implemented the repertoire of known bacteria of the human urinary tract. [ABSTRACT FROM AUTHOR]

Here we report the discovery of two Tupanvirus strains, the longest tailed Mimiviridae members isolated in amoebae. Their genomes are 1.44-1.51 Mb linear double-strand DNA coding for 1276-1425 predicted proteins. Tupanviruses share the same ancestors with mimivirus lineages and these giant viruses present the largest translational apparatus within the known virosphere, with up to 70 tRNA, 20 aaRS, 11 factors for all translation steps, and factors related to tRNA/mRNA maturation and ribosome protein modification. Moreover, two sequences with significant similarity to intronic regions of 18 S rRNA genes are encoded by the tupanviruses and highly expressed. In this translation-associated gene set, only the ribosome is lacking. At high multiplicity of infections, tupanvirus is also cytotoxic and causes a severe shutdown of ribosomal RNA and a progressive degradation of the nucleus in host and non-host cells. The analysis of tupanviruses constitutes a new step toward understanding the evolution of giant viruses. [ABSTRACT FROM AUTHOR]

Clonostachys rosea is a mycoparasitic fungus that can control several important plant diseases. Here, we report on the genome sequencing of C. rosea and a comparative genome analysis, in order to resolve the phylogenetic placement of C. rosea and to study the evolution of mycoparasitism as a fungal lifestyle. The genome of C. rosea is estimated to 58.3 Mb, and contains 14,268 predicted genes. A phylogenomic analysis shows that C. rosea clusters as sister taxon to plant pathogenic Fusarium species, with mycoparasitic/saprotrophic Trichoderma species in an ancestral position. A comparative analysis of gene family evolution reveals several distinct differences between the included mycoparasites. Clonostachys rosea contains significantly more ATP-binding cassette (ABC) transporters, polyketide synthases, cytochrome P450 monooxygenases, pectin lyases, glucose-methanol-choline oxidoreductases, and lytic polysaccharide monooxygenases compared with other fungi in the Hypocreales. Interestingly, the increase of ABC transporter gene number in C. rosea is associated with phylogenetic subgroups B (multidrug resistance proteins) and G (pleiotropic drug resistance transporters), whereas an increase in subgroup C (multidrug resistance-associated proteins) is evident in Trichoderma virens. In contrast with mycoparasitic Trichoderma species, C. rosea contains very few chitinases. Expression of six group B and group G ABC transporter genes was induced in C. rosea during exposure to the Fusarium mycotoxin zearalenone, the fungicide Boscalid or metabolites from the biocontrol bacterium Pseudomonas chlororaphis. The data suggest that tolerance toward secondary metabolites is a prominent feature in the biology of C. rosea. [ABSTRACT FROM PUBLISHER]

Background Saprophytic filamentous fungi are ubiquitous micro-organisms that play an essential role in photosynthetic carbon recycling. The wood-decayer Pycnoporus cinnabarinus is a model fungus for the study of plant cell wall decomposition and is used for a number of applications in green and white biotechnology. Results The 33.6 megabase genome of P. cinnabarinus was sequenced and assembled, and the 10,442 predicted genes were functionally annotated using a phylogenomic procedure. Indepth analyses were carried out for the numerous enzyme families involved in lignocellulosic biomass breakdown, for protein secretion and glycosylation pathways, and for mating type. The P. cinnabarinus genome sequence revealed a consistent repertoire of genes shared with wood-decaying basidiomycetes. P. cinnabarinus is thus fully equipped with the classical families involved in cellulose and hemicellulose degradation, whereas its pectinolytic repertoire appears relatively limited. In addition, P. cinnabarinus possesses a complete versatile enzymatic arsenal for lignin breakdown. We identified several genes encoding members of the three ligninolytic peroxidase types, namely lignin peroxidase, manganese peroxidase and versatile peroxidase. Comparative genome analyses were performed in fungi displaying different nutritional strategies (white-rot and brown-rot modes of decay). P. cinnabarinus presents a typical distribution of all the specific families found in the white-rot life style. Growth profiling of P. cinnabarinus was performed on 35 carbon sources including simple and complex substrates to study substrate utilization and preferences. P. cinnabarinus grew faster on crude plant substrates than on pure, mono- or polysaccharide substrates. Finally, proteomic analyses were conducted from liquid and solid-state fermentation to analyze the composition of the secretomes corresponding to growth on different substrates. The distribution of lignocellulolytic enzymes in the secretomes was strongly dependent on growth conditions, especially for lytic polysaccharide mono-oxygenases. Conclusions With its available genome sequence, P. cinnabarinus is now an outstanding model system for the study of the enzyme machinery involved in the degradation or transformation of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

Understanding the evolutionary plasticity of the genome requires a global, comparative approach in which genetic events are considered both in a phylogenetic framework and with regard to population genetics and environmental variables. In the mechanisms that generate adaptive and non-adaptive changes in genomes, segmental duplications (duplication of individual genes or genomic regions) and polyploidization (whole genome duplications) are well-known driving forces. The probability of fixation and maintenance of duplicates depends on many variables, including population sizes and selection regimes experienced by the corresponding genes: a combination of stochastic and adaptive mechanisms has shaped all genomes. A survey of experimental work shows that the distinction made between fixation and maintenance of duplicates still needs to be conceptualized and mathematically modeled. Here we review the mechanisms that increase or decrease the probability of fixation or maintenance of duplicated genes, and examine the outcome of these events on the adaptation of the organisms. [ABSTRACT FROM AUTHOR]

Reconstructing the evolutionary history of all species is an essential objective for evolutionary biologists. Much effort has been devoted to ancestral genome reconstruction. Numbered genome sequencing of current and extinct organisms enables evolutionary biologists to compare genomic data and reconstruct ancestral genomes. Long-term conservation of karyotype, gene order or gene sequence are clues to the heritage of each species and these data can be used by evolutionary biologists to synthesize distant ancestral genomes. In this review, we referred to the recent advances in ancestral genomes reconstruction and the insight it gives on genome evolution. Special attention is devoted to the use of this knowledge to understand the evolution of the immune system genes. [Copyright &y& Elsevier]

Giant viruses have been isolated and characterized in different environments, expanding our knowledge about the biology of these unique microorganisms. In the last 2 years, a new group was discovered, the cedratviruses, currently composed of only two isolates and members of a putative new family, "Pithoviridae," along with previously known pithoviruses. Here we report the isolation and biological and genomic characterization of two novel cedratviruses isolated from samples collected in France and Brazil. Both viruses were isolated using Acanthamoeba castellanii as a host cell and exhibit ovoid particles with corks at either extremity of the particle. Curiously, the Brazilian cedratvirus is ~20% smaller and presents a shorter genome of 460,038 bp, coding for fewer proteins than other cedratviruses. In addition, it has a completely asyntenic genome and presents a lower amino acid identity of orthologous genes (~73%). Pangenome analysis comprising the four cedratviruses revealed an increase in the pangenome concomitant with a decrease in the core genome with the addition of the two novel viruses. Finally, phylogenetic analyses clustered the Brazilian virus in a separate branch within the group of cedratviruses, while the French isolate is closer to the previously reported Cedratvirus lausannensis. Taking all together, we propose the existence of a second lineage of this emerging viral genus and provide new insights into the biodiversity and ubiquity of these giant viruses. IMPORTANCE Various giant viruses have been described in recent years, revealing a unique part of the virosphere. A new group among the giant viruses has recently been described, the cedratviruses, which is currently composed of only two isolates. In this paper, we describe two novel cedratviruses isolated from French and Brazilian samples. Biological and genomic analyses showed viruses with different particle sizes, genome lengths, and architecture, revealing the existence of a second lineage of this new group of giant viruses. Our results provide new insights into the biodiversity of cedratviruses and highlight the importance of ongoing efforts to prospect for and characterize new giant viruses. [ABSTRACT FROM AUTHOR]