Microbial diversity and functional gene profiling of cold-adaptive soil-microbiomes from Tullu-Dimtu Mountain, Ethiopia

Tullu-Dimtu Mountain, located in the Bale Mountains of the Oromia National Regional State in South-Eastern Ethiopia, is one of the country’s highest and coldest environments. Despite its extreme conditions, this region remains largely unexplored and is expected to host cold-adapted microorganisms with significant genetic and biotechnological potential. This study aimed to investigate the microbial diversity and functional gene profile of soil microbiomes from Tullu-Dimtu Mountain. Metagenomic DNA was extracted from homogenized soil samples collected from the site and sequenced using a high-throughput shotgun sequencing platform. Taxonomic analysis revealed a diverse microbial community, dominated by bacteria (95%), with smaller proportions of Archaea (1%), Eukaryota (0.03%), and viruses (0.1%), based on the Micro-NR database. Among the bacterial phyla, Pseudomonadota was the most abundant followed by Acidobacteriota, Verrucomicrobiota, Bacteroidota, and Gemmatimonadota. Functional annotation using the KEGG, eggNOG, and CAZy databases identified 120,534, 273,351, and 30,053 functional genes, respectively. Genes involved in carbohydrate, amino acid and energy metabolism (KEGG level 2) were particularly prevalent. Overall, the findings highlight Tullu-Dimtu Mountain as a rich reservoir of cold-adapted microbial communities and diverse functional genes, with promising potential for the discovery of natural products and enzymes for biotechnological applications.