biostudies-literatureFujita SInstitute for Fermentation OsakaEhime UniversityJapan Society for the Promotion of Science107505https://www.ebi.ac.uk/biostudies/studies/S-EPMC11298593biostudies-literatureUnknown300(8)Archaeosine (G⁺) is an archaea-specific tRNA modification synthesized via multiple steps. In the first step, archaeosine tRNA guanine transglucosylase (ArcTGT) exchanges the G15 base in tRNA with 7-cyano-7-deazaguanine (preQ₀). In Euryarchaea, preQ₀15 in tRNA is further modified by archaeosine synthase (ArcS). Thermococcus kodakarensis ArcS catalyzes a lysine-transfer reaction to produce preQ₀-lysine (preQ₀-Lys) as an intermediate. The resulting preQ₀-Lys15 in tRNA is converted to G⁺15 by a radical S-adenosyl-L-methionine enzyme for archaeosine formation (RaSEA), which forms a complex with ArcS. Here, we focus on the substrate tRNA recognition mechanism of ArcS. Kinetic parameters of ArcS for lysine and tRNA-preQ<The Journal of biological chemistryArcS from Thermococcus kodakarensis transfers L-lysine to preQ₀ nucleoside derivatives as minimum substrate RNAs.PMC11298593JP24K09381JP20H03211G-2022-2-052Fujita SYamagami RYokogawa THirata AOka NHori HKawamura TSugio YfalseArcS from Thermococcus kodakarensis transfers L-lysine to preQ₀ nucleoside derivatives as minimum substrate RNAs.Archaeosine (G⁺) is an archaea-specific tRNA modification synthesized via multiple steps. In the first step, archaeosine tRNA guanine transglucosylase (ArcTGT) exchanges the G15 base in tRNA with 7-cyano-7-deazaguanine (preQ₀). In Euryarchaea, preQ₀15 in tRNA is further modified by archaeosine synthase (ArcS). Thermococcus kodakarensis ArcS catalyzes a lysine-transfer reaction to produce preQ₀-lysine (preQ₀-Lys) as an intermediate. The resulting preQ₀-Lys15 in tRNA is converted to G⁺15 by a radical S-adenosyl-L-methionine enzyme for archaeosine formation (RaSEA), which forms a complex with ArcS. Here, we focus on the substrate tRNA recognition mechanism of ArcS. Kinetic parameters of ArcS for lysine and tRNA-preQ<2024-01-01T00:00:00Z2024 Jun2025-04-26T05:37:47.724Z2025-04-06T11:32:39.548ZS-EPMC112985933894412210.1016/j.jbc.2024.107505