title: Factors controlling aminoacyl-transfer-ribonucleic acid synthesis in vitro by a plant system.
abstract: 1. Factors affecting aminoacyl-tRNA synthesis in vitro by cell-free preparations from bean leaves were investigated. 2. Evidence was obtained that optimum concentrations as well as correct ratios of Mg(2+) and ATP are required for aminoacyl-tRNA synthesis in the bean-leaf system. 3. The results indicated that pH is a controlling factor having differential effects on the formation of individual aminoacyl-tRNA species. The possible micro-regulatory function of pH in protein synthesis in vivo is discussed with special reference to alanyl-tRNA formation. 4. Very low rates of alanine-stimulated pyrophosphate exchange were observed in the absence of tRNA. This observation is discussed relative to proposals about the mechanism of aminoacyl-tRNA synthesis.
mesh_terms: D000255:Adenosine Triphosphate; D000409:Alanine; D000596:Amino Acids / Q000378:metabolism; D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism*; D002247:Carbon Isotopes; D002474:Cell-Free System; D002736:Chloroplasts; D003593:Cytoplasm; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008274:Magnesium; D010710:Phosphates / Q000378:metabolism; D010944:Plants / Q000378:metabolism*; D011188:Potassium; D012343:RNA, Transfer / Q000096:biosynthesis*; D013696:Temperature; D014443:Tyrosine
chemical_list: D000596:Amino Acids; D002247:Carbon Isotopes; D010710:Phosphates; D014443:Tyrosine; D000255:Adenosine Triphosphate; D012343:RNA, Transfer; D000604:Amino Acyl-tRNA Synthetases; D008274:Magnesium; D000409:Alanine; D011188:Potassium