The glycyl-tRNA synthetases differ even among the eubacteria in oligomeric structure. In Escherichia coli and most others, it is a heterodimer of two alpha chains and two beta chains, encoded by tandem genes. The genes are similar, but fused, in Chlamydia trachomatis. By contrast, the glycyl-tRNA synthetases of Thermus thermophilus and of archaea and eukaryotes differ considerably; they are homodimeric, mutually similar, and not detected by this model. [Protein synthesis, tRNA aminoacylation]
Jiyao W et al.(2023). "The conserved domain database in 2023.",