Aspartyl-tRNA synthetase (AspRS)

Aspartyl-tRNA synthetase is an essential enzyme that catalyzes the covalent attachment of the amino acid aspartic acid to its corresponding tRNA (tRNA^Asp) in a two-step reaction utilizing ATP, forming Asp-tRNA^Asp, a prerequisite for incorporating aspartic acid during ribosomal protein synthesis[4][5][7][8]. It belongs to the class II aminoacyl-tRNA synthetases, characterized by conserved structural motifs (class IIb subclass) and shared mechanisms that distinguish it from class I enzymes[1][2][3]. The enzyme is a homodimer, with specific domains to recognize both aspartic acid and its cognate tRNA, and is found in all domains of life, with some forms able to aminoacylate both tRNA^Asp and tRNA^Asn, especially in archaea and bacteria[2][5][6]. In eukaryotes, particularly humans, the cytosolic form is a component of the multi-tRNA synthetase complex and may also participate in additional, non-canonical signaling roles[4]. It is a validated antimicrobial drug target due to its essentiality and differences between microbial and human forms that can be exploited for selective inhibition[5][6].

Other names

AspRSAspartate--tRNA ligaseDRS (in human, for cytoplasmic form)Aspartyl-tRNA ligaseAsxRS (for non-discriminating forms)

Competitive inhibition of aspartyl-AMP formation Prevention of aminoacylation of tRNA, thus halting protein synthesis Selective targeting can differentiate between bacterial/parasite AspRS and the human enzyme