Search results for "Bacterial genome size"
showing 10 items of 40 documents
Yaws re-emergence and bacterial drug resistance selection after mass administration of azithromycin: a genomic epidemiology investigation
2020
Summary Background In a longitudinal study assessing the WHO strategy for yaws eradication using mass azithromycin treatment, we observed resurgence of yaws cases with dominance of a single JG8 sequence type and emergence of azithromycin-resistant Treponema pallidum subspecies pertenue (T p pertenue). Here, we analyse genomic changes in the bacterial population using samples collected during the study. Methods We did whole bacterial genome sequencing directly on DNA extracted from 37 skin lesion swabs collected from patients on Lihir Island, Papua New Guinea, between April 1, 2013, and Nov 1, 2016. We produced phylogenies and correlated these with spatiotemporal information to investigate t…
Assembly methods for nanopore-based metagenomic sequencing: a comparative study
2019
ABSTRACTBackgroundMetagenomic sequencing has lead to the recovery of previously unexplored microbial genomes. In this sense, short-reads sequencing platforms often result in highly fragmented metagenomes, thus complicating downstream analyses. Third generation sequencing technologies, such as MinION, could lead to more contiguous assemblies due to their ability to generate long reads. Nevertheless, there is a lack of studies evaluating the suitability of the available assembly tools for this new type of data.FindingsWe benchmarked the ability of different short-reads and long-reads tools to assembly two different commercially available mock communities, and observed remarkable differences i…
Impact of barley (Hordeum vulgare L.) transgenic line H228.2A on substrate and rhizosphere microorganisms and the possibility of horizontal gene tran…
2013
Numerous investigations have been carried out to determine the impact of genetically modified plants, such as potato, maize, alfalfa and tobacco, on soil microorganisms and the results are contradictory. We applied classical microbiology methods to study quantitative changes of bacterial and fungal abundance in substrate and rhizosphere from barley (Hordeum vulgare L.) transgenic line H228.2A containing Rpg1 and bar genes, and its parent nontransgenic variety ‘Golden Promise’. In addition, molecular biology methods were used to determine, if horizontal gene transfer from barley transgenic line to soil bacteria has occurred under experimental conditions by screening bacterial genomes for the…
Mining virulence genes using metagenomics.
2011
When a bacterial genome is compared to the metagenome of an environment it inhabits, most genes recruit at high sequence identity. In free-living bacteria (for instance marine bacteria compared against the ocean metagenome) certain genomic regions are totally absent in recruitment plots, representing therefore genes unique to individual bacterial isolates. We show that these Metagenomic Islands (MIs) are also visible in bacteria living in human hosts when their genomes are compared to sequences from the human microbiome, despite the compartmentalized structure of human-related environments such as the gut. From an applied point of view, MIs of human pathogens (e.g. those identified in enter…
Genomic Analysis of Bacterial Outbreaks
2016
The study of outbreaks of infectious diseases has been revolutionized by the current availability of fast and efficient, high-throughput methods capable of yielding the nucleotide sequence of complete genomes of viruses and bacteria within a few days, or even hours. These methods are replacing previous molecular techniques which have been used for the past 30 years, although many of them are still the usual approach for many such investigations. Here we review the major technologies currently in use for high-throughput sequencing of bacterial genomes emphasizing their advantages and drawbacks for the analysis of outbreaks. The use of more efficient methods does not necessarily mean that all…
A genomic epidemiology investigation of yaws re-emergence and bacterial drug resistance selection
2020
Abstract Background In a longitudinal study assessing the WHO strategy for yaws eradication using mass azithromycin treatment, we observed resurgence of yaws cases with dominance of a single JG8 sequence type and emergence of azithromycin-resistant Treponema pallidum. Here, we analyse genomic changes in the bacterial population using samples collected during the study. Methods We performed whole bacterial genome sequencing directly on DNA extracted from 37 lesion swabs collected from patients on Lihir Island, Papua New Guinea, between 2013 and 2016. We produced phylogenies and correlated these with temporo-spatial information to investigate the source of new cases and the emergence of five …
Deciphering the role of insertion sequences in the evolution of bacterial epidemic pathogens with panISa software
2020
Next-generation sequencing (NGS) is now widely used in microbiology to explore genome evolution and the structure of pathogen outbreaks. Bioinformatics pipelines readily detect single-nucleotide polymorphisms or short indels. However, bacterial genomes also evolve through the action of small transposable elements called insertion sequences (ISs), which are difficult to detect due to their short length and multiple repetitions throughout the genome. We designed panISa software for the ab initio detection of IS insertions in the genomes of prokaryotes. PanISa has been released as open source software (GPL3) available from https://github.com/bvalot/panISa. In this study, we assessed the utilit…
A mathematical method for determining genome divergence and species delineation using AFLP.
2002
The delineation of bacterial species is presently achieved using direct DNA-DNA relatedness studies of whole genomes. It would be helpful to obtain the same genomically based delineation by indirect methods, provided that descriptions of individual genome composition of bacterial genomes are obtained and included in species descriptions. The amplified fragment length polymorphism (AFLP) technique could provide the necessary data if the nucleotides involved in restriction and amplification are fundamental to the description of genomic divergences. Firstly, in order to verify that AFLP analysis permits a realistic exploration of bacterial genome composition, the strong correspondence between …
Mobile genetic element proliferation and gene inactivation impact over the genome structure and metabolic capabilities of Sodalis glossinidius, the s…
2010
Abstract Background Genome reduction is a common evolutionary process in symbiotic and pathogenic bacteria. This process has been extensively characterized in bacterial endosymbionts of insects, where primary mutualistic bacteria represent the most extreme cases of genome reduction consequence of a massive process of gene inactivation and loss during their evolution from free-living ancestors. Sodalis glossinidius, the secondary endosymbiont of tsetse flies, contains one of the few complete genomes of bacteria at the very beginning of the symbiotic association, allowing to evaluate the relative impact of mobile genetic element proliferation and gene inactivation over the structure and funct…
Genome degeneration and adaptation in a nascent stage of symbiosis
2014
Symbiotic associations between animals and microbes are ubiquitous in nature, with an estimated 15% of all insect species harboring intracellular bacterial symbionts. Most bacterial symbionts share many genomic features including small genomes, nucleotide composition bias, high coding density, and a paucity of mobile DNA, consistent with long-term host association. In this study, we focus on the early stages of genome degeneration in a recently derived insect-bacterial mutualistic intracellular association. We present the complete genome sequence and annotation of Sitophilus oryzae primary endosymbiont (SOPE). We also present the finished genome sequence and annotation of strain HS, a close…