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Boury, C.

Publications and source records attributed to Boury, C..

4 recordsLinked to original sources

Sequencing, de novo assembly of Ludwigia plastomes, and comparative analysis within the Onagraceae family

The Onagraceae family, which belongs to the order Myrtales, consists of approximately 657 species and 17 genera, including the genus Ludwigia L., which is comprised of 82 species. There are few genomic resources for Onagraceae, which limits phylogenetic and population genetics, as well as genomic studies. In this study, new complete plastid genomes of Ludwigia grandiflora subps. hexapetala (Lgh) and Ludwigia peploides subsp montevidensis (Lpm) were generated using a combination of different sequencing technologies. These plastomes were then compared to the published Ludwigia octovalvis (Lo) plastid genome, which was re-annotated by the authors. We initially sequenced and assembled the chloroplast (cp) genomes of Lpm and Lgh using a hybrid strategy. We observed the existence of two Lgh haplotypes and two potential Lpm haplotypes. Lgh, Lpm, and Lo plastomes were similar in terms of genome size, gene number, structure, and inverted repeat (IR) boundaries, comparable to other species in the Myrtales order. A total of 45 to 65 SSRs (simple sequence repeats), were detected, depending on the species, with the majority consisting solely of A and T, which is common among angiosperms. Four chloroplast genes (matK, accD, ycf2 and ccsA) were found under positive selection pressure, which is commonly associated with plant development, and especially in aquatic plants such as Lgh, and Lpm. Our hybrid sequencing approach revealed the presence of two Lgh plastome haplotypes which will help to advance phylogenetic and evolutionary studies, not only specifically for Ludwigia, but also the Onagraceae family and Myrtales order. To enhance the robustness of our findings, a larger dataset of chloroplast genomes would be beneficial.

genomics↗

Comparative genomics of Mycoplasma feriruminatoris, a fast-growing pathogen of wild Caprinae

Mycoplasma feriruminatoris is a fast-growing Mycoplasma species isolated from wild Caprinae and first described in 2013. M. feriruminatoris isolates have been associated with arthritis, keratoconjunctivitis, pneumonia and septicemia, but were also recovered from apparently healthy animals. To better understand what defines this species, we performed a genomic survey on 14 strains collected from free-ranging or zoo-housed animals between 1987 and 2017. The average chromosome size of the M. feriruminatoris strains was 1,040 {+/-} 0,024 kbp, with 24% G+C and 852 {+/-} 31 CDS. The core genome and pan-genome of the M. feriruminatoris species contained 628 and 1,312 protein families, respectively. The M. feriruminatoris strains displayed a relatively closed pan-genome, with many features and putative virulence factors shared with species from the M. mycoides cluster, including the MIB-MIP Ig cleavage system, a repertoire of DUF285 surface proteins and a complete biosynthetic pathway for galactan. M. feriruminatoris genomes were found to be mostly syntenic, although repertoires of mobile genetic elements, including Mycoplasma Integrative and Conjugative Elements, insertion sequences, and a single plasmid varied. Phylogenetic- and gene content analyzes confirmed that M. feriruminatoris was closer to the M. mycoides cluster than to the ruminant species M. yeatsii and M. putrefaciens. Ancestral genome reconstruction showed that the emergence of the M. feriruminatoris species was associated with the gain of 17 gene families, some of which encode defense enzymes and surface proteins, and the loss of 25 others, some of which are involved in sugar transport and metabolism. This comparative study suggests that the M. mycoides cluster could be extended to include M. feriruminatoris. We also find evidence that the specific organization and structure of the DnaA boxes around the oriC of M. feriruminatoris may contribute to drive the remarkable fast growth of this minimal bacterium.

microbiology↗

Chromosomal rearrangements but no change of genes and transposable elements repertoires in an invasive forest-pathogenic fungus

AO_SCPLOWBSTRACTC_SCPLOWChromosomal rearrangements have been largely described among eukaryotes, and may have important consequences on evolution of species. High genome plasticity has been often reported in Fungi, which may explain their apparent ability to quickly adapt to new environments. Cryphonectria parasitica, causing the Chestnut blight disease, is an invasive fungal pathogen species associated with several recent host shifts during its successive introductions from Asia to North America and Europe. Previous cytological karyotyping and genomic studies suggested several chromosomal rearrangements which remains to be described in detail for this species. A serious limitation for valid genome comparisons is the access to robust genome assemblies that usually contain genomic regions of low complexity. We present a new de novo whole-genome assembly obtained from a new method of DNA extraction and long-reads sequencing Nanopore technology obtained from a Japanese isolate sampled in the native area of the species. The comparison with a recently published reference genome revealed stable gene and transposable elements (TEs) repertoires. We also showed that the C. parasitica genome is lowly compartmentalized, with a poor association between TEs and genes, such as those potentially involved in host interactions (i.e., genes coding for small secreted proteins or for secondary metabolites). This genome comparison, however, detected several large chromosomal rearrangements that may have important consequences in gene regulations and sexual mating in this invasive species. This study opens the way for more comparisons of high-quality assembled genomes, and questions the role of structural variations in the invasive success of this fungal pathogen species.

genomics↗

Fast sequence-based microsatellite genotyping development workflow for any non-model species

Application of high-throughput sequencing technologies to microsatellite genotyping (SSRseq) has been shown to remove many of the limitations of electrophoresis-based methods and to refine inference of population genetic diversity and structure. We present here a streamlined SSRseq development workflow that includes microsatellite development, multiplexed marker amplification and sequencing, and automated bioinformatics data analysis. We illustrate its application to five groups of species across phyla (fungi, plant, insect and fish) with different levels of genomic resource availability. We found that relying on previously developed microsatellite assay is not optimal and leads to a resulting low number of reliable locus being genotyped. In contrast, de novo ad hoc primer designs gives highly multiplexed microsatellite assays that can be sequenced to produce high quality genotypes for 20 to 40 loci. We highlight critical upfront development factors to consider for effective SSRseq setup in a wide range of situations. Sequence analysis accounting for all linked polymorphisms along the sequence, quickly generates a powerful multi-allelic haplotype-based genotypic dataset, calling to new theoretical and analytical frameworks to extract more information from multi-nucleotide polymorphism marker systems.

genetics↗