TRNA Modification Landscapes in Streptococci: Shared Losses and Clade-Specific Adaptations.

ABSTRACT: tRNA modifications are central to bacterial translational control. Here, we integrated genetics, mass spectrometry, epitranscriptomics, and comparative genomics to map the tRNA modification genes of the Gram-positive pathogens Streptococcus mutans and Streptococcus pneumoniae. Both species show a marked loss of modifications dependent on Fe-S enzymes, consistent with a broader trend of Fe-S enzyme reduction in Streptococcus central metabolism. In addition, the D, m¹A, m⁷G, t⁶A, and i⁶A modifications were mapped in S. pneumoniae tRNAs, and we confirmed that a unique DusB1 enzyme is responsible for the insertion of all the detectable D modifications. We uncovered differences in queuosine (Q) metabolism: while S. mutans s

SUBMITTER: Tsui HT 

PROVIDER: S-EPMC12632869 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature