Bacteria of the genus Thioalkalivibrio can be found in soda lakes. These lakes are naturally alkaline and hypersaline environments, with a pH ranging from 9.5 to 10.5. In soda lakes are a lot of different stress factors, like arsenic and uranium. Thioalkalivibrio needs to adapt continuously to changing conditions and to resistant to metals and unknown antibiotics. In this study, the bacteria of Thioalkalivibrio was adapted to 2 different kinds of antibiotics, ampicillin and streptomycin. The bacteria adapted from 0.1 µg/mL to 0.8 µg/mL of ampicillin and from 1.0 µg/mL to 8.0 µg/mL of streptomycin. The bacteria are most likely not adapted to ampicillin because of fast degradation in the medium was found. Also during growth with sodium, there was no difference between adapted and non-adapted cultures. However, it is likely that the bacteria did adapted to streptomycin. The bacteria showed difference in growth when sodium was present between the adapted and non-adapted cultures. Changes in the Rep-pcr profiles for all cultures which grew with ampicillin were detected. No changes were found in the rep-PCR profiles for all cultures which grew with streptomycin. Higher relative expression of arcB was found in cultures that were adapted to ampicillin. For further research, transcriptomics could be used to obtain a complete picture of the gene expression changes.