Biology subjects

Harmel, M.

Publications and source records attributed to Harmel, M..

3 recordsLinked to original sources

bioRxiv2026

A new automated pipeline for whole genome shotgun sequencing analysis and hazard characterization of microbial pesticides

Microbial pesticides are increasingly important for sustainable crop protection, yet hazard analysis and risk assessment remain challenging and require specific characterization of properties relevant to both safety and biological activity. Whole-genome sequencing (WGS) can support the identification of microorganisms at high resolution and characterize potential hazards associated with infectivity, pathogenicity, antimicrobial resistance, and toxic metabolite production. However, the routine use of WGS in this context requires accessible, reproducible, and interpretable workflows. Here, we present a publicly available web-based workflow for WGS-supported hazard analysis of microbial biocontrol agents. The workflow accepts assembled genomes as well as short-read, long-read and hybrid sequencing data, and performs genome quality assessment, taxonomic assignment, genome annotation, AMR detection, mobile-element screening, pathogenicity prediction and secondary-metabolite analysis, and compiles the results into an HTML report. For bacterial agents, we implement a transparent rule-based risk-classification module integrating taxonomic identity, PathogenFinder2 predictions, CARD/RGI resistance evidence, WHO priority taxa, and medically important antimicrobial categories. Secondary-metabolite assessment combines antiSMASH with local BLAST searches and EFSA-aligned identity/coverage thresholds to support product-level interpretation of biosynthetic gene clusters. Comparison with the currently used MOpS workflow developed by EFSA demonstrates the added benefits of the proposed workflow for a guided hazard analysis of microbial pesticides. The workflow is intended as a community-accessible pre-assessment tool that complements regulatory platforms by improving transparency, reproducibility, and early identification of potential hazards in microbial biocontrol candidates, envisioned to make WGS an integral part of the risk assessment of microbial pesticides. Key pointsO_LIThe RATION-GUI provides a public, reproducible workflow for whole-genome sequencing- supported hazard characterization of bacterial and fungal microbial pesticides. C_LIO_LIThe workflow integrates genome quality, taxonomy, annotation, antimicrobial resistance, pathogenicity-related evidence, mobile elements, and secondary-metabolite potential. C_LIO_LIDomain-specific outputs are translated into structured hazard indicators, evidence summaries, and recommended follow-up actions without replacing expert regulatory judgment. C_LIO_LICase studies demonstrate how the workflow improves transparency, traceability, and interpretation of genomic evidence for microbial pesticide risk assessment. C_LI

bioinformatics↗

bioRxiv2026

Taxonomic Description of Uncultured Cyanobacteria from Extreme Habitats through Genome-Based Classification

Cyanobacteria form a morphologically and phylogenetically diverse group of oxygenic phototrophic bacteria inhabiting a wide range of environments, including extreme habitats such as hot springs and volcanic steam vents. Many lineages, particularly those from these extreme environments, remain uncultured and are known only from metagenome-assembled genomes (MAGs), limiting their integration into formal taxonomy. Analysis of 46 steam vent associated samples from Hawai i using 16S rRNA amplicon sequencing revealed that cyanobacteria dominate these communities. Gloeobacter kilaueensis dominated pit-like environments with low-light conditions, while Leptolyngbyaceae and other families are more dominant in structured soil and wall communities. We further reconstructed 38 high-quality cyanobacterial MAGs and incorporated them into a phylogenomic analysis comprising 343 cyanobacterial genomes, followed by genome-based comparisons against 9,026 reference genomes. This revealed eight novel species and one novel genus spanning five orders: Chroococcidiopsidales, Leptolyngbyales, Nostocales, Oculatellales, and Oscillatoriales. Following SeqCode guidelines, we provide the first formal taxonomic descriptions of cyanobacterial MAGs and propose guidelines for integrating genome-based and cultivated material. These findings highlight Hawaiian steam vents as hotspots of previously uncharacterized cyanobacterial diversity and underscore the importance of genome-based nomenclature.

genomics↗

bioRxiv2025

A FAIR Amplicon Sequencing Workflow for Long-term Environmental Monitoring

Antarctica represents one of the last pristine environments on Earth, providing a unique opportunity to to study the effects of climate change and anthropogenic activities. Ice-free areas, such as the inland nunataks of the Sor Rondane Mountains (SRM), host unique terrestrial and lacustrine ecosystems, of which the simplified food webs rely almost exclusively on microbial primary production. Because of their small size, low productivity and hence low biomass, these microbial communities are fragile. Seven SRM sites were selected to be part of the Antarctic Specially Protected Area (ASPA) 179. The MonASPA project has established an environmental monitoring program to evaluate the effectiveness of the management plan approved by the Antarctic Treaty System for these areas. A key component of MonASPA is the long-term monitoring of microbial biodiversity using 16S rRNA amplicon sequencing. To ensure consistent operation over decades, we developed the Reproducible Amplicon Sequencing Pipeline for Antarctic Monitoring (RASPAM), which is built on Apptainer containers and Nextflow workflows. RASPAM implements Amplicon Sequence Variants (ASVs) and Zero-radius Operational Taxonomic Units (ZOTUs) to provide high-resolution taxonomic affiliation. It incorporates, in addition to the SILVA database, a taxonomically curated 16S rRNA database for cyanobacteria and enables comparisons against NCBI databases to facilitate the identification of rare prokaryotic strains in environmental samples. RASPAM is Findable, Accessible, Interoperable, and Reproducible (FAIR) and represents a robust tool for long-term monitoring of microbial communities in Antarctic and other extreme environments.

bioinformatics↗