Methionyl tRNA Synthetase 2, Mitochondrial (MARS2)

MARS2 encodes a deduced 593-amino acid protein with an 18-amino acid mitochondrial import signal sequence. The protein shares a high degree of identity with methionyl-tRNA synthetases from other mammals, but is less well conserved with the corresponding enzymes of lower eukaryotes and does not share considerable sequence similarity to the human cytoplasmic MetRS. The human mtMetRS protein and the E. coli homolog share 19% sequence identity. The domain organization of human mtMetRS closely resembles that of the S. cerevisiae and C. albicans mitochondrial MetRSs. Human mtMetRS contains the signature sequences HIGH and KMSKS that are present in all class I synthetases as well as many of the residues that have been proposed to contribute to a universal core in MetRS of all organisms.