Gene Organization, Properties and Specificity of 'Escherichia coli' TRNA (Transfer Ribonucleic Acids) Pseudouridine Synthase. 1

摘要

The transfer ribonucleic acids of coliform bacteria contain 7 sites where pseudouridine modifications occur. Three of these (residues 38-40 in the anticodon loop and stem) are formed by the enzyme, tRNA synthase I (PSUI). The hisT gene which encodes PSUE, is part of a multigene operon in E. coli and is adjacent to and upstream gene for a 36.4kd polypeptide if unknown function. The DNA sequence of a 2.3kb insert of the hisT operon has been determined and amino acid sequences deduced for both proteins. The two genes have overlapping translational signals and show markedly different codon usage, which may account for their differential expression.