From deep-sea vents to other harsh habitats, researchers have discovered vast microbial resources rich in novel genes and biosynthetic clusters, and used AI-guided screening to identify peptide candidates that could fuel the next wave of antibiotic discovery.
Research: Extremophile Microbiome Catalog (EEMC): A global resource for microbial diversity and antimicrobial discovery. Image credit: Galwis / Shutterstock
In a recent study published in the journal nature communicationsresearchers introduced the Extreme Environment Microbiome Catalog (EEMC), a large-scale resource designed to uncover the hidden microbial diversity of Earth’s most extreme habitats.
By reconstructing more than 78,000 genomes from thousands of metagenomes and isolates, the research team uncovered vast previously uncharacterized genetic and biosynthetic potential. Remarkably, this catalog enabled the identification of thousands of candidate antimicrobial peptides (cAMPs), many of which exhibited in vitro activity against difficult-to-treat Gram-negative pathogens, highlighting the promise of EEMC as a powerful platform for next-generation antimicrobial discovery. This study provides a large-scale integrated resource to study the microbiome of extreme environments.
Microorganisms living in extreme environments provide a rich yet largely untapped source of novel metabolites with potential biomedical value. Advances in sequencing and metagenomics have improved access to uncultured microorganisms, but most studies are small scale and limited to specific habitats, leaving global diversity and biosynthetic capacity poorly characterized. This gap is especially critical as the threat of antimicrobial resistance increases and antibiotic discovery slows. While genome mining and artificial intelligence are accelerating the search for antimicrobial peptides, challenges remain, including limited datasets, overlooked toxicity, and incomplete description of post-translational modifications, highlighting the need for more comprehensive and integrative approaches.
Extreme environment metagenomic research design
In this study, researchers systematically collected and reanalyzed metagenomic data from extreme environments around the world to build a comprehensive genomic resource. This dataset spans a variety of habitats, including the deep ocean, cryosphere, hypersaline, geothermal, subsurface, and hyperarid systems, capturing a wide range of environmental variation.
The team collected and curated over 2,200 publicly available metagenomes, along with over 3,000 isolated genomes, including newly generated samples from cold seep sediments. We reconstructed and purified over 78,000 bacterial and archaeal genomes using established quality standards. The researchers then clustered these genomes into operational taxonomic units at the species level and performed taxonomic annotation and phylogenetic analysis to map diversity and distribution across environments.
The team then predicted open reading frames and built a large nonredundant gene catalog, which was then extensively functionally annotated using multiple public databases. To assess biosynthetic potential, they identified over 160,000 biosynthetic gene clusters (BGCs) and assessed their novelty through comparative and clustering approaches. They specifically focused on ribosomal synthesis and post-translationally modified peptide (RiPP) clusters, given their relevance to antimicrobial drug discovery.
To identify promising therapeutic candidates, researchers integrated machine learning tools with protein-based large-scale language models (LLMs) to predict antimicrobial activity and toxicity. After screening thousands of candidates, we synthesized a core peptide that was selected for experimental validation. The research team evaluated antibacterial activity, minimum inhibitory concentration (MIC), and cytotoxicity, and further investigated the structure and mechanism of the peptide using imaging, membrane integrity assays, and other biophysical techniques.
Consequences of microbial diversity in extreme environments
Researchers established the EEMC as a large-scale genomic analysis resource by reconstructing 78,213 microbial genomes from diverse extreme habitats and clustering them into 32,715 species-level groups. Remarkably, more than 86% of these species were not mapped to comparative reference genome sets, revealing more than 20,000 potentially novel species and significantly expanding global microbial diversity.
This catalog also includes approximately 4 billion unique genes, with approximately 19.21% remaining unannotated in the referenced databases. Additionally, the team identified over 163,000 biosynthetic gene clusters (BGCs) by assessing novelty through gene cluster family and clan analysis, highlighting immense biosynthetic potential that remains largely unexplored.
The research team observed strong habitat-specific patterns. Environments such as the deep ocean and the cryosphere are major sources of novelty, with the deep ocean contributing the greatest absolute number of novel genes and gene clusters. Many of the genes identified were related to stress adaptation, transport, and metabolic regulation. This finding reflects how microorganisms survive under extreme conditions while producing a variety of secondary metabolites.
Discovery results of candidate antimicrobial peptides
Using protein LLM, researchers identified 3,032 cAMPs that were predicted to be nontoxic. Remarkably, 84% of the set of 100 peptides synthesized for experimental testing inhibited bacterial growth. Importantly, the 50 candidates tested in mammalian cells showed low cytotoxicity. Some peptides showed potent activity against difficult-to-treat Gram-negative bacteria, and some peptides showed low MICs.
Structural and mechanistic analyzes revealed that many active peptides adopt an α-helical structure and act by disrupting bacterial membranes. Importantly, one of the lead candidates, cAMP_81, showed a decreased propensity to induce resistance over time. This finding highlights the promise of these early-stage unmodified peptide scaffolds as next-generation antimicrobial agents derived from untapped extremophile microbiomes.
Implications for biotechnology in extreme environments
This study positions the Extremophile Microbiome Catalog as a global reference resource for investigating microbial diversity and biosynthetic potential in Earth’s most extreme habitats. This study highlights the untapped potential of extremophiles in drug discovery by revealing vast taxonomic novelty and demonstrating the successful discovery of nontoxic antimicrobial peptides. Importantly, our findings suggest that current sampling is only beginning to capture this diversity, and point to a much larger reservoir that remains unexplored.
Looking to the future, integrating advanced sequencing technologies, artificial intelligence and targeted cultivation strategies will be key to unlocking this potential. Expanding functional validation, including mature post-translationally modified RiPPs, structural confirmation, and in vivo testing, may further accelerate the discovery of novel therapeutics, enzymes, and bioactive compounds, positioning EEMC as an important platform for future innovations in biotechnology and biomedicine.
Reference magazines:
- Jiang, P. et al. (2026). Extremophile Microbiome Catalog (EEMC): A global resource for microbial diversity and antimicrobial discovery. Nature Communications. DOI: 10.1038/s41467-026-71145-0, https://www.nature.com/articles/s41467-026-71145-0
