Seryl-tRNA synthetase specificity for tRNASec in bacterial sec biosynthesis.
FERNANDES, Adriano de Freitas; SERRÃO, Vitor Hugo Balasco; SCORTECCI, Jessica Fernandes; THIEMANN, Otávio Henrique.
FERNANDES, Adriano de Freitas; SERRÃO, Vitor Hugo Balasco; SCORTECCI, Jessica Fernandes; THIEMANN, Otávio Henrique.
Abstract: tRNA synthetases are responsible for decoding the molecular information, from codons to amino acids. SeryltRNA synthetase (SerRS), besides the five isoacceptors of tRNASer, recognizes tRNA[Ser]Sec for the incorporation of selenocysteine (Sec, U) into selenoproteins. The selenocysteine synthesis pathway is known and is dependent on several protein-protein and protein-RNA interactions. Those interactions are not fully described, in particular, involving tRNA[Ser]Sec and SerRS. Here we describe the molecular interactions between the Escherichia coli SeryltRNA synthetase (EcSerRS) and tRNA[Ser]Sec in order to determine their specificity, selectivity and binding order, leading to tRNA aminoacylation. The dissociation constant of EcSerRS and tRNA[Ser]Sec was determined as (126 ± 20) nM. We also demonstrate that EcSerRS binds initially to tRNA[Ser]Sec in the presence of ATP for further recognition by E. coli selenocysteine synthetase (EcSelA) for Ser to Sec conversion. The proposed studies clarify the mechanism of tRNA[Ser]Sec incorporation in Bacteria as well as of other domains of life.
@article={002998193,author = {FERNANDES, Adriano de Freitas; SERRÃO, Vitor Hugo Balasco; SCORTECCI, Jessica Fernandes; THIEMANN, Otávio Henrique.},title={Seryl-tRNA synthetase specificity for tRNASec in bacterial sec biosynthesis},journal={Biochimica et Biophysica Acta: proteins and proteomics},note={v. 1868, n. 8, p. 140438-1-140438-8},year={2020}}