Classification of MAGs associated with trace gas metabolism in volcanic soils named following SeqCode rules

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).