title: Chromosomal location and cloning of the gene (trmD) responsible for the synthesis of tRNA (m1G) methyltransferase in Escherichia coli K-12.
abstract: The trmD gene, which governs the formation of 1-methyl-guanosine(m1G) in transfer ribonucleic acid (tRNA), has been located by phage P1 transduction at 56 min on the chromosomal map of Escherichia coli. Cotransduction to tyrA at 56 min is 80%. From the Clarke and Carbon collection a ColE1-tyrA+ hybrid plasmid was isolated, which carried the trmD+ gene and was shown to over-produce the tRNA(m1G)methyltransferase. By subcloning restriction enzyme fragments in vitro, the trmD+ gene was located to a 3.4 kb DNA fragment 6.5 kb clockwise from the tyrA+ gene. The mutation trmD1, which renders the tRNA(m1G)methyltransferase temperature-sensitive both in vivo and in vitro could be complemented by trmD+ plasmids. These results suggest that the gene trmD+ is the structural gene for the tRNA(m1G)methyltransferase (EC 2.1.1.3.1).
mesh_terms: D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D005796:Genes; D005798:Genes, Bacterial; D005838:Genotype; D009154:Mutation; D010641:Phenotype; D010957:Plasmids; D012359:tRNA Methyltransferases / Q000235:genetics*
chemical_list: D012359:tRNA Methyltransferases; C036950:tRNA (guanine-N1-)-methyltransferase; D004262:DNA Restriction Enzymes