Heterogeneity of RNA polymerase in Bacillus subtilis: evidence for an additional sigma factor in vegetative cells.
Heterogeneity of RNA polymerase in Bacillus subtilis: evidence for an additional sigma factor in vegetative cells.
复制标题
枯草芽孢杆菌中RNA聚合酶的异质性：营养细胞中存在额外西格玛因子的证据。
DOI：
10.1073/pnas.78.5.2762
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发表时间：
1981
影响因子：
11.1
通讯作者：
Chamberlin,MJ
中科院分区：
文献类型：
--
作者：
Wiggs,JL;Gilman,MZ;Chamberlin,MJ
来自植物生长细胞的枯草芽孢杆菌RNA聚合酶（核苷三磷酸：RNA核苷酸转移酶，EC 2.7.7.6）的制剂含有少量活性（B.枯草杆菌RNA聚合酶全酶II），与正常B相比，其显示出对T7噬菌体DNA的独特启动子特异性。枯草杆菌全酶（全酶I）并且缺乏正常的σ亚基[Jaehning，J.A.，Wiggs，J. L. & Chamberlin，M. J.（1979）Proc.Natl. Acad. Sci. USA 76，5470-5474]。通过肝素-琼脂糖层析，我们获得了全酶II级分，其没有可检测到的全酶I活性，这是通过它们在我们测试的任何模板上都没有利用全酶I的启动子位点来判断的。这些馏分与B的活性要高得多。枯草芽孢杆菌DNA与T7 DNA或其它异源模板相比。这种高度的特异性允许鉴定含有B克隆片段的质粒。具有全酶II的强启动子位点的枯草杆菌DNA。这些启动子位点根本不被B使用。枯草杆菌RNA聚合酶全酶I。全酶II的特异性由Mr为28，000的肽决定，这是通过肽与特异性全酶II活性的共纯化和当分离的肽加入B时全酶II启动子特异性的重建来判断的。枯草杆菌核心聚合酶。因此，28，000 Mr肽似乎是一个σ因子，其决定了与RNA聚合酶全酶I和所有其他已知细菌RNA聚合酶不同的启动子特异性。
Preparations of Bacillus subtilis RNA polymerase (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6) from vegetatively growing cells contain small amounts of an activity (B. subtilis RNA polymerase holoenzyme II) that shows a unique promoter specificity with T7 bacteriophage DNA as compared with the normal B. subtilis holoenzyme (holoenzyme I) and lacks the normal sigma subunit [Jaehning, J. A., Wiggs, J. L. & Chamberlin, M. J. (1979) Proc. Natl. Acad. Sci. USA 76, 5470-5474]. By heparin-agarose chromatography we have obtained holoenzyme II fractions that have no detectable holoenzyme I activity as judged by their failure to utilize promoter sites for holoenzyme I on any template we have tested. These fractions are far more active with B. subtilis DNA than with T7 DNA or other heterologous templates. This high degree of specificity has allowed identification of plasmids containing cloned fragments of B. subtilis DNA that bear strong promoter sites for holoenzyme II. These promoter sites are not used at all by B. subtilis RNA polymerase holoenzyme I. The specificity of holoenzyme II is dictated by a peptide of Mr 28,000 as judged by copurification of the peptide with specific holoenzyme II activity and by reconstitution of the holoenzyme II promoter specificity when the isolated peptide is added to B. subtilis core polymerase. Hence the 28,000 Mr peptide appears to be a sigma factor that determines a promoter specificity distinct from that of RNA polymerase holoenzyme I and all other known bacterial RNA polymerases.