期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1975
卷号:72
期号:4
页码:1589-1593
DOI:10.1073/pnas.72.4.1589
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:An RNA polymerase (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6 ) has been purified from phage-SP01-infected Bacillus subtilis that copies RNA almost exclusively from the heavy strand of native SP01 DNA, the DNA strand from which "middle" and "late" classes of RNA are copied in vivo. Hybridization-competition established that this RNA polymerase termed enzyme A, preferentially synthesizes middle RNA in vitro. Enzyme A contains beta',beta, alpha, and two newly identified host polypeptides, variation of (21,500 daltons) and omega (11,000 daltons). All of these polypeptides are associated with highly purified RNA polymerase from uninfected bacteria. In addition, enzyme A contains phage-induced subunits of 26,000, 24,000, and 13,500 daltons. Enzyme A lacks sigma polypeptide, and strand-selective transcription by this enzyme is resistant to anti-sigma antibody. A reconstitution experiment strongly suggests that the host variation of protein is required in addition to a phage-induced subunit(s) (or an unidentified phage-induced modification) for strand-selective transcription of SP01 middle genes in vitro.