RRC ID 35257
Author Anton BP, Russell SP, Vertrees J, Kasif S, Raleigh EA, Limbach PA, Roberts RJ.
Title Functional characterization of the YmcB and YqeV tRNA methylthiotransferases of Bacillus subtilis.
Journal Nucleic Acids Res.
Abstract Methylthiotransferases (MTTases) are a closely related family of proteins that perform both radical-S-adenosylmethionine (SAM) mediated sulfur insertion and SAM-dependent methylation to modify nucleic acid or protein targets with a methyl thioether group (-SCH(3)). Members of two of the four known subgroups of MTTases have been characterized, typified by MiaB, which modifies N(6)-isopentenyladenosine (i(6)A) to 2-methylthio-N(6)-isopentenyladenosine (ms(2)i(6)A) in tRNA, and RimO, which modifies a specific aspartate residue in ribosomal protein S12. In this work, we have characterized the two MTTases encoded by Bacillus subtilis 168 and find that, consistent with bioinformatic predictions, ymcB is required for ms(2)i(6)A formation (MiaB activity), and yqeV is required for modification of N(6)-threonylcarbamoyladenosine (t(6)A) to 2-methylthio-N(6)-threonylcarbamoyladenosine (ms(2)t(6)A) in tRNA. The enzyme responsible for the latter activity belongs to a third MTTase subgroup, no member of which has previously been characterized. We performed domain-swapping experiments between YmcB and YqeV to narrow down the protein domain(s) responsible for distinguishing i(6)A from t(6)A and found that the C-terminal TRAM domain, putatively involved with RNA binding, is likely not involved with this discrimination. Finally, we performed a computational analysis to identify candidate residues outside the TRAM domain that may be involved with substrate recognition. These residues represent interesting targets for further analysis.
Volume 38(18)
Pages 6195-205
Published 2010-10
DOI 10.1093/nar/gkq364
PII gkq364
PMID 20472640
PMC PMC2952846
MeSH Adenosine / analogs & derivatives Amino Acid Sequence Bacillus subtilis / enzymology* Bacterial Proteins / chemistry Bacterial Proteins / genetics Bacterial Proteins / metabolism* Heat-Shock Proteins / chemistry Heat-Shock Proteins / genetics Heat-Shock Proteins / metabolism* Molecular Sequence Data Mutation Phenotype Protein Structure, Tertiary RNA, Transfer / chemistry RNA, Transfer / metabolism* Recombinant Fusion Proteins / chemistry Recombinant Fusion Proteins / metabolism Sulfurtransferases / chemistry Sulfurtransferases / genetics Sulfurtransferases / metabolism*
IF 11.561
Times Cited 20
Prokaryotes B. subtilis MGNA-C496(YQEVd)