In transfer RNA many different modified nucleosides are found, especially in the anticodon region. tRNA (guanine (N1))-methyltransferase (TrmD) is one of several nucleases operating together with the tRNA-modifying enzymes before the formation of the mature tRNA. TrmD catalyses the S-adenosyl-methionine(AdoMet) dependent It methlyation of guanosine(G) to N1-methylguanine (1-methylguanosine (m1G)) at position 37 of tRNAs that read CUN (leucine), CCN(proline), and CGG (arginine) codons. The presence of m1G improves the cellular growth rate and the polypeptide steptime and also prevents the tRNA from shifting the reading frame.
Defined by 4 residues: PRO:A-109 [auth A-89]GLU:A-136 [auth A-116]ARG:A_2-174 [auth A_2-154]ASP:A_2-189 [auth A_2-169]