Aminoacyl-tRNA synthesis in methanogenic Archaea

Aminoacyl-tRNA synthetases (AARSs) are essential for faithful translation of the genetic code and have long been studied intensively. Major discoveries explained basic principles of how amino acids are paired to their cognate tRNAs to ensure high fidelity of translation. However, advances in genomics instigated identification of novel enzymes and pathways to aminoacyl-tRNA synthesis, in that respect methanogenic Archaea are particularly prominent, most of which possess non-canonical routes to synthesis of Ash-tRNA, Cys-tRNA, Gln-tRNA and Lys-tRNA. Additionally, some methanogenic seryl-tRNA synthetases are only marginally related to their homologues outside the archaeal kingdom, while other AARSs exhibit multiplicity of their genes (LysRS, SerRS, PheRS). Therefore, methanogens represent an exciting group of organisms regarding aminoacyl-tRNA synthesis, attesting to high degree of evolutionary diversity.