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Information × Registration Number 0214U005450, 0109U007245 , R & D reports Title Study on molecular basis of fidelity of the genetic code translation during of aminoacyl-tRNA formation. popup.stage_title Head Tukalo Mykhaylo, Доктор біологічних наук Registration Date 30-12-2014 Organization Institute of molecular biology & genetics popup.description2 The editing mechanisms investigations of the misacylation products by LeuRS (Leu-tRNA-synthetase) from T.thermophilus, ProRS (Pro-tRNA-synthetase) from E.faecalis and DTD (D-tyrosyl-tRNA-deacylase) from T.thermophilus were performed. The editing activity of LeuRSTT was shown against natural non-protein-producing analogues of Leu (norvaline and norleucine) using biochemical methods, genetic engineering, site-directed mutagenesis, modifications of tRNA, computer modeling and quantum-chemical calculations. The editing of protein-producing amino acids is performed mainly in the catalytic domain of LeuRSTT in the pre-transfer manner, precisely, through the hydrolysis of appropriate aminoacyl-adenylates. tRNA-assisted mechanism of pre-transfer editing for LeuRS from prokaryotes has been proposed. tRNA-dependent pre-transfer editing by ProRS from E.faecalis, mediated by 2'- and 3'-hydroxyl groups of A76 tRNAPro was firstly identified for structural class II of aminoacyl-tRNA-synthetases. Structural and functional organization of the editing active site of ProRSEF in the complex with Ala-tRNAPro was shown; the catalytic mechanism of its deacylation was detected. The most important functional element of this mechanism is 2'-OH A76 Ala-tRNAPro, which plays a key role in substrate-assisted catalysis. D-tyrosyl-tRNA-deacylase was shown to hydrolyze incorrectly formed D-tyrosyl-tRNATyr. The structure of the complex of D-Tyr-tRNATyr-deacylase from T.thermophilus and D-tyrosyl-A76-tRNATyr was studied by molecular dynamics technique. Key amino acids of the enzyme active site were identified for further learning of the mechanism of deacylation by site-directed mutagenesis. Product Description popup.authors Бояршин Костянтин Сергійович Гудзеpа Ольга Йосипівна Кpикливий Іван Андрійович Коваленко Оксана Петрівна Яpемчук Ганна Дмитрівна popup.nrat_date 2020-04-02 Close