Volume 48, Issue 4, July 2025, 126622Author links open overlay panel, , Abstract

Trace gas metabolism is important for nutrient flow in all ecosystems, particularly volcanic ecosystems. Microbes in volcanic ecosystems are among the early colonisers and can play key roles in ecological succession. Here, we describe the taxonomic and functional characteristics of two new metagenome-assembled genomes (MAGs), one belonging to Bacteria (MAG_1957-2.1) and one to Archaea (MAG_C2-3), retrieved from soils in volcanoes located in Chile (Llaima) and the USA (Kilauea), respectively. MAG_1957-2.1 has a genome size of 6.36 Mb with 96.21 % completeness. MAG_C2-3 has a genome size of 3.02 Mb with 97.57 % completeness. Phylogenetic analyses of the bacterial MAGs placed MAG_1957-2.1 in the class Ktedonobacteria, while the archaeal MAG_C2-3 was placed in the class Nitrososphaeria. Functional characterisation for potential trace gas metabolism showed that MAG_1957-2.1 contains a coxL gene encoding the large subunit of form I carbon monoxide dehydrogenase (CoxL), which is associated with the oxidation of carbon monoxide (CO). It also contains the form I cox gene cluster with a coxMSL arrangement. On the other hand, MAG_C2-3 contains gene subunit A (amoA) as well as subunit B (amoB), which encode for ammonia monooxygenase, the enzyme that catalyses the oxidation of ammonia. Based on the sequence characteristics and phylogenomic analyses we propose the names Paraktedonobacter carboxidivorans sp. nov for MAG_1957-2.1 and Nitrososphaera maunauluensis sp. nov for MAG_C2-3. The names are proposed following the rules of the published Code of Nomenclature of Prokaryotes Described from Sequence Data (SeqCode).

Keywords

Volcanic soils

CO-dehydrogenase

Trace gases

SeqCode

Chloroflexota

Archaea

Data availabilityBacterial MAG_1957-2.1 has been deposited in the NCBI-SRA under the bioproject accession number PRJNA602601 (Hernández et al., 2020b). Archaeal MAG-C2-3 has been deposited in the NCBI-SRA under the bioproject accession number PRJNA1096838. The 16S rRNA gene sequences of these MAGs were deposited in the NCBI-SRA under SRA accession numbers SRR32116977 for MAG_1957-2.1 and SRR32116972 for MAG MAG-C2-3.

© 2025 The Authors. Published by Elsevier GmbH.