Biology subjects

Brugere, J.-F.

Publications and source records attributed to Brugere, J.-F..

4 recordsLinked to original sources

bioRxiv2025

Fast and sensitive multiplexed diagnostic system enabled by real-time solid-phase PCR assay

Simultaneous identification of multiple nucleic acid targets is pivotal for high-throughput analysis in clinical diagnostics. Unfortunately, conventional PCR offers limited multiplexing capability due to issues like primer interference, fluorescence spectral overlaps and instrumentation complexity. Solid-phase PCR (SP-PCR), in which primers are physically separated on a solid support, has emerged as an alternative strategy for detection of multiple targets in parallel. However, SP-PCR has been suffering from low efficiency, long reaction time, inability for real-time signal monitoring and accurate quantification, which greatly restricts their applications in multiplexed assays. In this study, we presented for the first time a compact and portable flow-through SP-PCR platform to permit rapid, highly efficient and quantitative solid-phase amplification. We designed an integrated platform comprising a novel mechanically actuated valving system and a dual-chamber SP-PCR system to enable automated sample purification and amplification. Active oscillating the PCR solution between the chambers significantly enhanced the mass diffusion over the solid-phase array. Moreover, after each amplification cycle, the PCR solution was separated from the solid-phase-bound probes, thereby eliminating background signal interference and allowing for real-time monitoring of SP-PCR signals without the need for complex optical systems. The flow-through SP-PCR system demonstrated quantitative detection of five viral pathogens in a single reaction, with a limit of detection of 10 copies per reaction within 20 minutes. This platform provides a promising high-throughput, low-cost and simple-instrumentation multiplexed diagnostic system.

molecular biology↗

bioRxiv2021

Growth temperature is the principal driver of chromatinization in archaea

Across the tree of life, DNA in living cells is associated with proteins that coat chromosomes, constrain their structure and influence DNA-templated processes such as transcription and replication. In bacteria and eukaryotes, HU and histones, respectively, are the principal constituents of chromatin, with few exceptions. Archaea, in contrast, have more diverse repertoires of nucleoid-associated proteins (NAPs). The evolutionary and ecological drivers behind this diversity are poorly understood. Here, we combine a systematic phylogenomic survey of known and predicted NAPs with quantitative protein abundance data to shed light on the forces governing the evolution of archaeal chromatin. Our survey highlights the Diaforarchaea as a hotbed of NAP innovation and turnover. Loss of histones and Alba in the ancestor of this clade was followed by multiple lineage-specific horizontal acquisitions of DNA-binding proteins from other prokaryotes. Intriguingly, we find that one family of Diaforarchaea, the Methanomethylophilaceae, lacks any known NAPs. Comparative analysis of quantitative proteomics data across a panel of 19 archaea revealed that investment in NAP production varies over two orders of magnitude, from <0.02% to >5% of total protein. Integrating genomic and ecological data, we demonstrate that growth temperature is an excellent predictor of relative NAP investment across archaea. Our results suggest that high levels of chromatinization have evolved as a mechanism to prevent uncontrolled helix opening and runaway denaturation - rather than, for example, to globally orchestrate gene expression - with implications for the origin of chromatin in both archaea and eukaryotes.

evolutionary biology↗

bioRxiv2020

A comprehensive analysis of the global human gut archaeome from a thousand genome catalogue

The human gut microbiome plays an important role in health and disease, but the archaeal diversity therein remains largely unexplored. Here we report the pioneering analysis of 1,167 non-redundant archaeal genomes recovered from human gastrointestinal tract microbiomes across countries and populations. We identified three novel genera and 15 novel species including 52 previously unknown archaeal strains. Based on distinct genomic features, we warrant the split of the Methanobrevibacter smithii clade into two separate species, with one represented by the novel Candidatus M. intestini. Patterns derived from 1.8 million proteins and 28,851 protein clusters coded in these genomes showed substantial correlation with socio-demographic characteristics such as age and lifestyle. We infer that archaea are actively replicating in the human gastrointestinal tract and are characterized by specific genomic and functional adaptations to the host. We further demonstrate that the human gut archaeome carries a complex virome, with some viral species showing unexpected host flexibility. Our work furthers our current understanding of the human archaeome, and provides a large genome catalogue for future analyses to decipher its role and impact on human physiology. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=81 SRC="FIGDIR/small/392621v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@3e0060org.highwire.dtl.DTLVardef@8adb45org.highwire.dtl.DTLVardef@41c087org.highwire.dtl.DTLVardef@c6fdf9_HPS_FORMAT_FIGEXP M_FIG GRAPHICAL ABSTRACT C_FIG HIGHLIGHTSO_LIThe human gut archaeome analysis reveals a previously unseen active diversity C_LIO_LIThe most abundant methanogen, Methanobrevibacter smithii, splits into two species C_LIO_LIArchaeal protein catalogue can predict geography, demographics and health aspects C_LIO_LIHost-associated and environmental archaea show distinct genomic & functional traits C_LI

bioinformatics↗

bioRxiv2017

ASaiM: a Galaxy-based framework to analyze raw shotgun data from microbiota

BackgroundNew generation of sequencing platforms coupled to numerous bioinformatics tools has led to rapid technological progress in metagenomics and metatranscriptomics to investigate complex microorganism communities. Nevertheless, a combination of different bioinformatic tools remains necessary to draw conclusions out of microbiota studies. Modular and user-friendly tools would greatly improve such studies.\n\nFindingsWe therefore developed ASaiM, an Open-Source Galaxy-based framework dedicated to microbiota data analyses. ASaiM provides a curated collection of tools to explore and visualize taxonomic and functional information from raw amplicon, metagenomic or metatranscriptomic sequences. To guide different analyses, several customizable workflows are included. All workflows are supported by tutorials and Galaxy interactive tours to guide the users through the analyses step by step. ASaiM is implemented as Galaxy Docker flavour. It is scalable to many thousand datasets, but also can be used a normal PC. The associated source code is available under Apache 2 license at https://github.com/ASaiM/framework and documentation can be found online (http://asaim.readthedocs.io/)\n\nConclusionsBased on the Galaxy framework, ASaiM offers sophisticated analyses to scientists without command-line knowledge. ASaiM provides a powerful framework to easily and quickly explore microbiota data in a reproducible and transparent environment.

bioinformatics↗