Functionally critical residues in the aminoglycoside resistance-associated methyltransferase RmtC play distinct roles in 30S substrate recognition.

ABSTRACT: Methylation of the small ribosome subunit rRNA in the ribosomal decoding center results in exceptionally high-level aminoglycoside resistance in bacteria. Enzymes that methylate 16S rRNA on N7 of nucleotide G1405 (m⁷G1405) have been identified in both aminoglycoside-producing and clinically drug-resistant pathogenic bacteria. Using a fluorescence polarization 30S-binding assay and a new crystal structure of the methyltransferase RmtC at 3.14 Å resolution, here we report a structure-guided functional study of 30S substrate recognition by the aminoglycoside resistance-associated 16S rRNA (m⁷G1405) methyltransferases. We found that the binding site for these enzymes in the 30S subunit directly overlaps with that of a second family of aminoglycoside resistance-associated

SUBMITTER: Nosrati M 

PROVIDER: S-EPMC6873201 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature