Cloning and restriction mapping of the trmA gene coding for transfer ribonucleic acid (5-methyluridine)-methyltransferase in Escherichia coli K-12.
AUTOR(ES)
Ny, T
RESUMO
A hybrid plasmid from the Clarke and Carbon collection has been isolated. This plasmid carries the trmA gene of E. coli, which is necessary for the formation of 5-methyluridine (m5U,ribothymidine) present in all transfer ribonucleic acid (tRNA) chains of the organism so far sequenced. A restriction map of the argCBH-trmA regions is presented. By using cloning in vitro, the trmA gene was located on a 2.9-kilobase pair deoxyribonucleic acid (DNA) fragment. These results and comparison with lambda dargECBH transducing phages established the gene order: argECBH trmA bfe in the 88-min region of the E. coli chromosomal map. Plasmids carrying this 2.9-kilobase pair DNA fragment overproduce the enzyme tRNA(m5U)methyltransferase (EC 2.1.1.35) 20 to 40 times. When this 2.9-kilobase pair chromosomal DNA fragment was expressed in a minicell system, a polypeptide of a molecular weight of 42,000 was synthesized. This polypeptide was tentatively identified as the tRNA(m5U)methyltransferase. These results support the earlier suggestion that the trmA gene is the structural gene for the tRNA(m5U)methyltransferase.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=293980Documentos Relacionados
- Transductional mapping of gene trmA responsible for the production of 5-methyluridine in transfer ribonucleic acid of Escherichia coli.
- Growth Rate-Dependent Regulation of Transfer Ribonucleic Acid (5-Methyluridine)Methyltransferase in Escherichia coli B/r
- Structure and organization of the transfer ribonucleic acid genes of Escherichia coli K-12.
- Role of methionyl-transfer ribonucleic acid in the regulation of methionyl-transfer ribonucleic acid synthetase of Escherichia coli K-12.
- Genetic organization and transcription from the gene (trmA) responsible for synthesis of tRNA (uracil-5)-methyltransferase by Escherichia coli.