Metagenomic Analysis of Bacterial Communities in Waters of Lake Natron, Arusha, Tanzania

Abstract

Metagenomics involves genetic material extraction and sequencing directly from environmental samples in order to gain insights and relationships that exist between microbes and their surroundings. Few studies have been done in extreme environments including soda lakes such as Lake Natron which is found in Arusha region, Tanzania. This study recorded high pH and salinity values confirming the lake's extremity. Full-length 16S rRNA reads sequenced through PacBio was used to reveal first metagenomic snapshots of bacterial communities from 10 random points at the lake shoreline waters. The results showed the dominance of Proteobacteria and Firmicutes with relative abundances of 98.46% and 70.46, respectively. Alphaproteobacteria (93.59%), Bacteroidia (23.80%) and Bacilli (23.19%) were the most dominant classes. Oceanibaculaceae (52.43%), Rhizobiaceae (66.62%) and Izemoplasmataceae (12.50%) were the most dominant families. The dominant genera were Oceanibaculum (52.44%), Allorhizobium (65.59%) and Izimaplasma (12.50%), respectively. The diversity indices showed high level of community diversity, a large number of species, the presence of rare species and an even distribution of bacteria across the sampling points. While this study provides the first report on the occurrence of various taxa in Lake Natron, functional metagenomic analysis is recommended for further investigation of the ecological and biotechnological significance of the identified species.

Metagenomics; PacBio sequencing; bacteria diversity; Soda Lakes; Lake Natron