Accepted_test
In modern microbial ecology, two main approaches for studying microbiomes have emerged: metagenomics, based on whole-genome sequencing, and metabarcoding. Metabarcoding, while often considered less comprehensive than metagenomic analysis for assessing a community's metabolic potential, is becoming more viable due to new tools that greatly enhance its capabilities and affordability. In this context, we decided to compare the results of studies using these two approaches by examining the microbial communities of Shulgan-Tash Cave, located in the foothills of the Southern Urals. Caves are oligotrophic ecosystems characterized by moderately low temperatures, high humidity, and the absence of light; these conditions result in a limited number of community members, making caves a convenient model system.
For our comparative studies, we selected two biofilms: an azurite wall biofilm and a submerged aquatic biofilm from a cave lake, which differed significantly in composition and metabolic characteristics.
The metabarcoding method for rapid and inexpensive screening of samples was relevant for biofilms in oligotrophic habitats. Comparison of metabarcoding and metagenomics data showed similar results at the level of dominant taxa but differed in the abundance of minor representatives of biofilms. The correspondence between metabarcoding and metagenome data depended on the database used. A significant portion of the microbial community was not identified to the genus level by either method. Metagenomic analysis has been preferred for characterizing microbial community metabolism.