title: DNA-dependent RNA polymerase from Halobacterium halobium.
abstract: DNA-dependent RNA polymerase core enzyme was isolated from Halobacterium halobium. The purification is based on the finding that the enzyme is stable in 40% (v/v) glycerol, in the presence of 0.05 M MgCl2 and involves adsorption of contaminants to DEAE-cellulose, precipitation of the complex of polymerase with DNA by streptomycin sulfate, chromatography over Biogel and affinity chromatography over heparin-Sepharose or heparin-cellulose. The enzyme consists of four or five different subunits. The composition formula was estimated as (150000) (86000)2 (72000)2 (49000)3 or 2; there may be one or two different 49000-Mr subunits. RNA synthesis requires a template. Denatured DNA is more efficient than native DNA. The transcription of native DNA is specifically stimulated by the addition of a possibly sigma-like factor eluted from DEAE-cellulose. The fidelity of transcription is indicated by the absolute requirement for UTP besides ATP with poly[d(A-T)] as the template.
mesh_terms: D012321:DNA-Directed RNA Polymerases / Q000302:isolation & purification / Q000378:metabolism*; D006217:Halobacterium / Q000201:enzymology*; D007700:Kinetics; D046911:Macromolecular Substances; D008970:Molecular Weight; D013698:Templates, Genetic; D014158:Transcription, Genetic
chemical_list: D046911:Macromolecular Substances; D012321:DNA-Directed RNA Polymerases