title: A stopped-flow apparatus with light-scattering detection and its application to biochemical reactions.
abstract: A stopped-flow apparatus utilizing light-scattering for following the progress of a reaction is described. The method is applicable to all reactions that result in a significant change of the average molecular weight. It was possible due to several modifications of a conventional stopped-flow system to obtain a sensitivity comparable to that of commercial instruments for static light-scattering measurements. Experiments on three reactions are reported: association and dissociation of mercury ligands with DNA, dissociation of the dimers of DNA-dependent RNA polymerase, and complex formation of tRNA(Ser) (yeast) with the cognate aminoacyl-tRNA synthetase. The changes in the intensities of the scattered light are calculated and compared with the measured amplitudes.
mesh_terms: D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism; D000818:Animals; D001669:Biochemical Phenomena; D001671:Biochemistry; D002417:Cattle; D004247:DNA / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology; D007700:Kinetics; D007834:Lasers / Q000295:instrumentation; D008024:Ligands / Q000378:metabolism; D008027:Light; D008628:Mercury; D009991:Oscillometry; D012343:RNA, Transfer / Q000378:metabolism; D012542:Scattering, Radiation
chemical_list: D008024:Ligands; D004247:DNA; D012343:RNA, Transfer; D012321:DNA-Directed RNA Polymerases; D000604:Amino Acyl-tRNA Synthetases; D008628:Mercury