In most prokaryotes Asn-tRNA(Asn) and Gln-tRNA(Gln) are formed by amidation of aspartate and glutamate mischarged onto tRNA(Asn) and tRNA(Gln), respectively. Coexistence in the organism of mischarged Asp-tRNA(Asn) and Glu-tRNA(Gln) and the homologous Asn-tRNA(Asn) and Gln-tRNA(Gln) does not, however, lead to erroneous incorporation of Asp and Glu into proteins, since EF-Tu discriminates the mis...

Transfer RNAs (tRNAs) are one of the classical non-coding RNAs, with lengths of approximately 70–100 bases. The secondary structure of tRNAs can be represented as a cloverleaf with four stems, and the three-dimensional structure as an “L” shape. Historically, the basic function of the tRNAs as essential components of translation was established in the 1960s, when it was found that each tRNA is ...

We have developed three strategies to discriminate among the three types of tRNA genes with anticodon CAT (tRNA(Ile), elongator tRNA(Met) and initiator tRNA(fMet)) in bacterial genomes. With these strategies, we have classified the tRNA genes from 234 bacterial and several organellar genomes. These sequences, in an aligned or unaligned format, may be used for the identification and annotation o...

Transfer RNA from soybean (Glycine max) cotyledons was purified to homogeneity followed by the purification of the family of leucine tRNA via benzoylated diethylaminoethyl cellulose (BDC) chromatography. Nonacylated total purified tRNA was salicylhydroxamate (SHAM) modified by the phenoxyacetyl method and fractionated into three peaks on a BDC column. The first peak containing bulk tRNA with no...

Total transfer RNAs were extracted from highly purified potato mitochondria. From quantitative measurements, the in vivo tRNA concentration in mitochondria was estimated to be in the range of 60 microM. Total potato mitochondrial tRNAs were fractionated by two-dimensional polyacrylamide gel electrophoresis. Thirty one individual tRNAs, which could read all sense codons, were identified by amino...

U4 small nuclear RNA is essential for trans-splicing. Here we report the cloning of U4 snRNA gene from Leptomonas collosoma and analysis of elements controlling its expression. The trypanosome U4 RNA is the smallest known, it carries an Sm-like site, and has the potential for extensive intermolecular base pairing with the U6 RNA. Sequence analysis of the U4 locus indicates the presence of a tRN...

In many bacteria and archaea, an ancestral pathway is used where asparagine and glutamine are formed from their acidic precursors while covalently linked to tRNA(Asn) and tRNA(Gln), respectively. Stable complexes formed by the enzymes of these indirect tRNA aminoacylation pathways are found in several thermophilic organisms, and are called transamidosomes. We describe here a transamidosome form...

The suppression of an amber mutation in a permissive strain of Escherichia coli can be achieved by a new tRNA species, a suppressor tRNA (for a review, see Reference 1). The tyrosine amber suppressor tRNA arises from a redundant tRNA species in the Sustrain by a single base change in the anticodon (2). However, this may not be the only mechanism to generate suppressor tRNA species, as suggested...

Understanding the mechanistic basis of the disruption of tRNA genes, as manifested in the intron-containing and split tRNAs found in Archaea, will provide considerable insight into the evolution of the tRNA molecule. However, the evolutionary processes underlying these disruptions have not yet been identified. Previously, a composite genome of the deep-branching archaeon Caldiarchaeum subterran...

The suppression of an amber mutation in a permissive strain of Escherichia coli can be achieved by a new tRNA species, a suppressor tRNA (for a review, see Reference 1). The tyrosine amber suppressor tRNA arises from a redundant tRNA species in the Sustrain by a single base change in the anticodon (2). However, this may not be the only mechanism to generate suppressor tRNA species, as suggested...