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：12
页码：4886-4890
DOI：10.1073/pnas.72.12.4886
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：RNA polymerase (nucleosidetriphosphate: RNA nucleotidyltransferase, EC 2.7.7.6 ) was purified from rifampicin-resistant Bacillus subtilis, from both uninfected cells and cells infected with bacteriophage SP01. The enzyme from infected cells lacked all traces of the sigma subunit, contained several polypeptides absent from the enzyme made in uninfected cells, and had an altered template specificity in a transcription assay. A cell-free protein synthesizing system from Escherichia coli, when poisoned with rifampicin, was completely dependent on addition of either of these RNA polymerase preparations for DNA-dependent protein synthesis. Under these conditions, the SP01-modified RNA polymerase preferentially stimulated the synthesis of functional mRNA for the phage enzyme dCMP deaminase (deoxycytidylate aminohydrolase, EC 3.5.4.12 ), whereas unmodified B. subtilis RNA polymerase could stimulate synthesis of this mRNA in small quantity and only after prolonged incubation. This mRNA belongs to a class of phage transcripts (m) which cannot be transcribed in vivo in the absence of phage-specific protein synthesis.
