has participant hydron S-adenosyl-L-homocysteine zwitterion S-adenosyl-L-methionine zwitterion N(1)-methylguanosine 5'-monophosphate(1-) residue guanosine 5'-monophosphate(1-) residue tRNA (guanine) methyltransferase activity tRNA (guanosine(9)-N1)-methyltransferase activity https://github.com/geneontology/go-ontology/issues/26085 MetaCyc:RXN-12459 Reactome:R-HSA-6787591 GO:0052905 RHEA:43156 EC:2.1.1.221 Reactome:R-HSA-6786621 tRNA (guanine-N(1)-)-methyltransferase activity tRNA (guanosine(9)-N1-)-methyltransferase activity Catalysis of the reaction: guanosine9 in tRNA + S-adenosyl-L-methionine = H+ + N1-methylguanosine9 in tRNA + S-adenosyl-L-homocysteine. tRNA (guanosine(9)-N(1))-methyltransferase activity tRNA(m(1)G(9)/m(1)A(9))Mtase activity molecular_function tRNA(m(1)G(9)/m(1)A(9))-methyltransferase activity tRNA m(1)G(9)-methyltransferase activity tRNA (guanine(9)-N(1))-methyltransferase activity tRNA m(1)G(9) Mtase activity