While translational read-through of stop codons by suppressor tRNAs is common in many bacteria, archaea and eukaryotes, this phenomenon has not yet been observed in the α-proteobacterium Caulobacter crescentus. Based on a previous report that C. crescentus and Escherichia coli tRNA(His) have distinctive identity elements, we constructed E. coli tRNA(His) CUA, a UAG suppressor tRNA for C. cresce...

The complete mitochondrial genome of Chirolophis wui (Wang and Wang, 1935) was sequenced using the Illumina platform. sequence is 16,522 bp in length with 54% A+T content contains 13 protein coding genes (PCGs), 22 transfer RNA (tRNAs), 2 ribosomal (rRNAs), 1 control region (D-loop). H-strand 28 (12 PCGs, 14 tRNAs, rRNAs), whereas L-strand accommodates 9 (ND6 8 tRNAs). nucleotide composition C....

The initiation of protein synthesis by Streptococcus faecalis R grown in folate-free culture occurs without N-formylation or N-acylation of methionyl-tRNA(f) (Met). Methionyl-tRNA synthetase and methionyl-tRNA formyltransferase were partially purified from S. faecalis grown under normal culture conditions in the presence of folate (plus-folate); the general properties of the enzymes were determ...

A high level of accuracy during protein synthesis is considered essential for life. Aminoacyl-tRNA synthetases (aaRSs) translate the genetic code by ensuring the correct pairing of amino acids with their cognate tRNAs. Because some aaRSs also produce misacylated aminoacyl-tRNA (aa-tRNA) in vivo, we addressed the question of protein quality within the context of missense suppression by Cys-tRNA(...

In most bacteria, two tRNAs decode the four arginine CGN codons. One tRNA harboring a wobble inosine (tRNA(Arg)ICG) reads the CGU, CGC and CGA codons, whereas a second tRNA harboring a wobble cytidine (tRNA(Arg)CCG) reads the remaining CGG codon. The reduced genomes of Mycoplasmas and other Mollicutes lack the gene encoding tRNA(Arg)CCG. This raises the question of how these organisms decode CG...

This study is a consideration of the condition and distribution of tRNA in rabbit reticulocytes. Levels of tRNA aminoacylation by 18 different amino acids were determined by assaying tRNA resistance to periodate oxidation. The levels range from 71% aminoacylation for tRNA accepting glycine to 97% for tRNAs accepting leucine and phenylalanine, with most values being close to 90 %. Amounts of tRN...

BACKGROUND The addition of new amino acids to the genetic code of Escherichia coli requires an orthogonal suppressor tRNA that is uniquely acylated with a desired unnatural amino acid by an orthogonal aminoacyl-tRNA synthetase. A tRNA(Tyr)(CUA)-tyrosyl-tRNA synthetase pair imported from Methanococcus jannaschii can be used to generate such a pair. In vivo selections have been developed for sele...

SelB is a specialized translation elongation factor that delivers selenocysteyl-tRNA(Sec) (Sec-tRNA(Sec)) to the ribosome. Here we show that Sec-tRNA(Sec) binds to SelB.GTP with an extraordinary high affinity (K(d) = 0.2 pm). The tight binding is driven enthalpically and involves the net formation of four ion pairs, three of which may involve the Sec residue. The dissociation of tRNA from the t...

While a number of aminoacyl tRNA synthetase (aaRS):tRNA pairs have been engineered to alter or expand the genetic code, only the Methanococcus jannaschii tyrosyl tRNA synthetase and tRNA have been used extensively in bacteria, limiting the types and numbers of unnatural amino acids that can be utilized at any one time to expand the genetic code. In order to expand the number and type of aaRS/tR...

Radioactive O-phosphoryl-L-serine was detected after alkaline deacylation of rat and rooster liver [(3)H]seryl-tRNA acylated in vitro with homologous synthetases. Ribonuclease treatment of this tRNA yielded a compound with the properties of phosphoseryl-adenosine. Benzoylated DEAE-cellulose chromatography of seryl-tRNA yielded four distinct peaks, only one of which contained phosphoserine. A un...