title: RNA polymerase assembly in vitro. Temperature dependence of reactivation of denatured core enzyme.
abstract: The Escherichia coli RNA polymerase core molecule, after denaturation in 6 M guanidine hydrochloride, can be completely reactivated in the absence of sigma subunit. Reactivation is temperature dependent. At 4 degrees a renatured-inactive preparation is formed that has most of the secondary structure of the original native molecule but has a reduced sedimentation coefficient and a smaller Stokes radius and is, therefore, of lower molecular weight. Upon warming to 37 degrees the renatured-inactive preparation is converted in a time-dependent process to the renatured-active preparation, which has the same amount of secondary structure and same molecular weight as native RNA polymerase. Since the renatured-inactive material is probably composed of subunit assemblies and can be readily reactivated, it should be useful for studying the subunit interactions and control of assembly of RNA polymerase.
mesh_terms: D001665:Binding Sites; D002845:Chromatography; D002942:Circular Dichroism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D006146:Guanidines; D008970:Molecular Weight; D011489:Protein Denaturation; D013696:Temperature; D014158:Transcription, Genetic; D014461:Ultracentrifugation; D014466:Ultraviolet Rays
chemical_list: D006146:Guanidines; D012321:DNA-Directed RNA Polymerases