Comparative 16s metagenomic analysis of prokaryotic diversity in freshwater and permanent snow-line glacial lakes in Türkiye

Abstract

Freshwater lakes are critical to healthy ecosystems, providing vital services like drinking water and recreation for surrounding communities. Microorganisms within these ecosystems play essential roles, driving biogeochemical cycles for elements like carbon, nitrogen, and sulfur. This study utilized a metagenomic approach to examine the prokaryotic communities of three freshwater lakes in Türkiye: the Eber and Beyşehir lakes, located at close altitudes (967 m and 1,115 m, respectively), which serve as primary water sources for nearby communities, and Lake Uludag Buzlu (2,390 m) that lies at the permanent snow border within the Uludag glacial lake system. Metagenomics allowed us to identify species, genetic structures, and the functional roles of microorganisms. Employing high-throughput next-generation sequencing (NGS) technology, we analyzed 16S ribosomal DNA (rDNA) sequences (V3-V4 regions) from the lake samples. EzBioCloud software facilitated the analysis of prokaryotic diversity obtained using Illumina NovaSeq technology. While Eber and Beyşehir lakes had similar diversity, Bacillota dominated in the higher-altitude Lake Uludag Buzlu. Genus-level analysis revealed Parabacteroides as the most prevalent in Lake Uludag Buzlu, contrasting with Limnohabitans dominance in Lake Eber; Lake Beyşehir exhibited co-dominance of Limnohabitans and Planktophila.

Keywords

• freshwater lakes
• glacial lakes
• 16s metagenomics
• prokaryotic diversity
• high altitudeeco systems