The purified ermC methyltransferase described here incorporates two methyl groups per Bacillus subtilis 23S rRNA molecule in vitro. The Km for S-adenosyl-L-methionine was 12 microM, and for B. subtilis 23S rRNA the Km was 375 nM. In vivo methylation specified by several related resistance determinants prevented in vitro methylation by the ermC enzyme, suggesting that methylation specified by all of these determinants occurs at homologous sites. Since methyl groups were incorporated in protein-free 23S rRNA molecules, the structure of rRNA alone must contain sufficient information to specify the methylation site.
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http://dx.doi.org/10.1128/jb.169.8.3857-3860.1987 | DOI Listing |
The sarcin-ricin loop (SRL) is one of the most conserved segments of ribosomal RNA (rRNA). Translational GTPases (trGTPases), such as EF-G and EF-Tu and IF2, form contacts with the SRL that are critical for GTP hydrolysis and factor function. Previous studies showed that expression of 23S rRNA lacking the SRL confers a dominant lethal phenotype in E.
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Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.
Cyclic diguanosine monophosphate (c-di-GMP) is a ubiquitous bacterial secondary messenger with diverse functions. A previous Escherichia coli proteome microarray identified that c-di-GMP binds to the 23S rRNA methyltransferases RlmI and RlmE. Here we show that c-di-GMP inhibits RlmI activity in rRNA methylation assays, and that it modulates ribosome assembly in the presence of kanamycin.
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January 2025
Civil and Construction Engineering and Environmental and Ecological Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, Indiana, United States 47907. Electronic address:
This study evaluated microbial fitness under selective pressure of various erythromycin concentrations and the development of resistance genes in Escherichia coli (E. coli) and Enterococcus faecalis (E. faecalis).
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Faculty of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia.
Identification and analysis of repetitive elements (motifs) in DNA, RNA, and protein macromolecules is an important step in studying structure and functions of these biopolymers. Functional role of NA-BSE (non-adjacent base-stacking element, a widespread tertiary structure motif in various RNAs) in RNA-RNA interactions at various stages of the ribosome function during translation has been investigated in this work. Motifs of this type have been described to date that are reversibly formed during mRNA decoding, moving of the ribosome subunits relative to each other, and moving mRNA and tRNA along the ribosome during translocation.
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December 2024
Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babeș-Bolyai University, 1 M. Kogalniceanu Street, 400084 Cluj-Napoca, Romania.
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