The influence of salt concentration on CD spectra of tRNA and aminoacyl-tRNA synthetase.
The CD spectra of serine tRNA or seryl-tRNA synthetase were measured. The [theta] values at 210 nm were minimum at 50mM - 0.2M NaCl, at that concentration the velocity of aminoacylation was maximum. This results suggest that A . U and G . C base pairs loosened. The [theta] values at 200 nm decreased according to the decreasing of salt concentration, suggesting the decomposition of A . U base pairs. The CD spectra of seryl-tRNA synthetase at 210-240 nm were not changed in the range of 10mM-0.3M NaCl but the spectra at 260-290 nm showed minimum in the range between 50mM-0.2M NaCl. These results suggest that the influence of salt concentration on the velocity of aminoacylation depends on both the conformational changes of tRNA and seryl-tRNA synthetase.
D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism; D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D008099:Liver / Q000032:analysis; D009690:Nucleic Acid Conformation; D011487:Protein Conformation; D012343:RNA, Transfer; D012492:Salts; D012694:Serine; D012714:Serine-tRNA Ligase / Q000378:metabolism
D012492:Salts; D012694:Serine; D012343:RNA, Transfer; D000604:Amino Acyl-tRNA Synthetases; D012714:Serine-tRNA Ligase