Determination of microbial changes in freshwater mussel Unio stevenianus
(Krynicki, 1837) living in a river contaminated with sewage and
livestock waste by NGS
Abstract
1. The rise in human population has led to the expansion of settlements
and an increase in the types and amounts of wastes released into the
aquatic environment. Bivalves have an important place among the
invertebrate communities of freshwater environments. Mussels remove
suspended substances from the water and contribute significantly to the
regulation of the physical properties of water. 2. This study was
conducted to determine the microbiome load in the intestinal tissue of
the freshwater mussel Unio stevenianus (Bivalvia: Unionidae) living in
Karasu river. 3. Amplification of the V3-V4 region of the bacterial 16s
rRNA gene fragment was performed in tissue samples. Bacterial species
were divided into operational taxonomic units using the Kraken
metagenomics program. 4. The percentage bacterial distribution with the
highest reading sequence at the phylum level was determined as Bacillota
> Bacteroidota > Pseudomonadota >
Actinomycetota > Cyanobacteriota >
Campylobacterota > Fusobacteriota in Arısu samples; while
in Zeve samples, it was determined as Pseudomonadota >
Actinomycetota > Bacteroidota > Bacillota
> Cyanobacteriota > Campylobacterota. 5. The
detection of various bacterial phylum indicates that the water
environment in which the mussel samples were collected is exposed to a
large number of bacterial sources, especially domestic waste. The
continued existence of freshwater mussels is necessary for them to
fulfill their important duties in the ecosystem. To achieve this,
uncontrolled and untreated waste discharges should be abandoned.
Pollutants in the water and mussel populations should also be monitored
through a monitoring program.