the autism spectrum disorders (asd) are amongst the most heritable complex disorders. although there have been many efforts to locate the genes associated with asd risk, many has been remained to be disclosed about the genetics of asd. scrutiny's have only disclosed a small number of de novo and inherited variants significantly associated with susceptibility to asd. these only comprise a s...

Extracellular RNAs (exRNAs) including abundant full length tRNAs and tRNA fragments (tRFs) have recently garnered attention as a promising source of biomarkers novel mediator in cell-to-cell communication eukaryotes. Depending on the physiological state cells, tRNAs/tRFs are released to extracellular space either contained vesicles (EVs) or free, through mechanism that is largely unknown. In th...

The spread of drug-resistant Staphylococcus aureus (S. aureus) in hospitals and communities poses a serious medical threat. This study aimed to identify aminoacyl-tRNA synthetase inhibitors with antimicrobial activity against S. aureus. In silico structure-based drug screening using docking molecular dynamics simulations (MDS) was performed targeting metionyl-tRNA (saMetRS). Ten candidate compo...

Selenocysteine (Sec) biosynthesis in archaea and eukaryotes requires three steps: serylation of tRNA(Sec) by seryl-tRNA synthetase (SerRS), phosphorylation of Ser-tRNA(Sec) by O-phosphoseryl-tRNA(Sec) kinase (PSTK), and conversion of O-phosphoseryl-tRNA(Sec) (Sep-tRNA(Sec)) by Sep-tRNA:Sec-tRNA synthase (SepSecS) to Sec-tRNA(Sec). Although SerRS recognizes both tRNA(Sec) and tRNA(Ser) species, ...

Aminoacyl-tRNAs (aa-tRNAs) are the essential substrates for translation. Most aa-tRNAs are formed by direct aminoacylation of tRNA catalyzed by aminoacyl-tRNA synthetases. However, a smaller number of aa-tRNAs (Asn-tRNA, Gln-tRNA, Cys-tRNA and Sec-tRNA) are made by synthesizing the amino acid on the tRNA by first attaching a non-cognate amino acid to the tRNA, which is then converted to the cog...

The recent algorithm for five split tRNA-genes in N.equitans is new . It locates missing tRNA-trp, tRNA-imet, tRNA-glu and tRNA-his . But the split tRNA-trp(CCA) solution is anomalous ; the tRNA-imet lacks cognition elements for aminoacylation . In view therefore we present here alternate non-split composite solutions for tRNA-trp, tRNA-imet, tRNA-glu and tRNA-his .

We recently described an orthogonal initiator tRNA (itRNATy2) that can initiate protein synthesis with noncanonical amino acids (ncAAs) in response to the UAG nonsense codon. Here, we report a mutant of itRNATy2 (itRNATy2AUA) efficiently translation UAU tyrosine codon, giving rise proteins ncAA at their N-terminus. show that, cells expressing itRNATy2AUA, function as dual-use codon selectively ...

Archaea make glutaminyl-tRNA (Gln-tRNA(Gln)) in a two-step process; a non-discriminating glutamyl-tRNA synthetase (ND-GluRS) forms Glu-tRNA(Gln), while the heterodimeric amidotransferase GatDE converts this mischarged tRNA to Gln-tRNA(Gln). Many prokaryotes synthesize asparaginyl-tRNA (Asn-tRNA(Asn)) in a similar manner using a non-discriminating aspartyl-tRNA synthetase (ND-AspRS) and the hete...

The essential methanogen enzyme Sep-tRNA:Cys-tRNA synthase (SepCysS) converts O-phosphoseryl-tRNA(Cys) (Sep-tRNA(Cys)) into Cys-tRNA(Cys) in the presence of a sulfur donor. Likewise, Sep-tRNA:Sec-tRNA synthase converts O-phosphoseryl-tRNA(Sec) (Sep-tRNA(Sec)) to selenocysteinyl-tRNA(Sec) (Sec-tRNA(Sec)) using a selenium donor. While the Sep moiety of the aminoacyl-tRNA substrates is the same in...