title: Regulation of synthesis of methionyl-, prolyl-, and threonyl-transfer ribonucleic acid synthetases of Escherichia coli.
abstract: Proline- and threonine-restricted growth caused a three- to fourfold derepression of the differential rate of synthesis of the prolyl- and threonyl-transfer ribonucleic acid (tRNA) synthetases, respectively. Similarly, there was approximately a 24-fold derepression in the rate of synthesis of methionyl-tRNA synthetase during methionine restriction. Addition of the respective amino acids to such derepressed cultures resulted in a repression of synthesis of their cognate synthetases. These results support previous findings and further strengthen the idea that the formation of aminoacyl-tRNA synthetases is regulated by some mechanism which is mediated by the cognate amino acids.
mesh_terms: D000332:Aerobiosis; D000604:Amino Acyl-tRNA Synthetases / Q000096:biosynthesis*; D002247:Carbon Isotopes; D002474:Cell-Free System; D002499:Centrifugation, Density Gradient; D002586:Cesium; D002712:Chlorides; D003470:Culture Media; D004794:Enzyme Repression; D004926:Escherichia coli / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism; D008715:Methionine / Q000378:metabolism; D011392:Proline / Q000378:metabolism; D013912:Threonine / Q000378:metabolism
chemical_list: D002247:Carbon Isotopes; D002712:Chlorides; D003470:Culture Media; D002586:Cesium; D013912:Threonine; D011392:Proline; D008715:Methionine; D000604:Amino Acyl-tRNA Synthetases