The National Center for Biotechnology Information protein databases were accessed on 13 th of January, 2023. We used BLASTP with default parameters and 2-nitrotoluene dioxygenase (AAB40383.1) from Acidovorax sp. strain JS42 95 as a query sequence against two databases: non-redundant protein sequences (nr) and proteins from WGS metagenomic projects (env nr).