Horizontal transfer of post-translational modifiers brings evolutionary opportunity and challenges to a conserved translation factor

Our findings highlight that PTM systems introduced via HGT can have varied effects on host proteins. We found that different EF-P variants are impacted in different ways by off-target rhamnosylation. While some of these off-target reactions may present opportunities to develop novel, catalytically active PTMs, others are detrimental to the function of the modified EF-P. Our results emphasize the complexity of gene integration and functional compatibility in foreign genomic contexts.