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An Immunological Assay for the Sigma Subunit of RNA Polymerase in Extracts of Vegetative and Sporulating Bacillus subtilis 总被引:16,自引:2,他引:14
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Robert Tjian Richard Losick 《Proceedings of the National Academy of Sciences of the United States of America》1974,71(7):2872-2876
The activity of the sigma subunit of Bacillus subtilis RNA polymerase decreases markedly during the first hours of sporulation [T.G. Linn et al. (1973) Proc. Nat. Acad. Sci. USA 70, 1865-1869]. We have prepared antibody against RNA polymerase holoenzyme to determine the fate of sigma polypeptide during spore formation. This antiserum specifically and independently precipitates sigma and core polymerase from crude extracts of B. subtilis as judged by both sodium dodecyl sulfate and urea gel electrophoresis of the precipitates. We report that crude extracts of sporulating cells lacking sigma activity contain as much sigma polypeptide as extracts of vegetative cells. However, sigma polypeptide in extracts from sporulating cells is apparently only weakly associated with RNA polymerase, as indicated by the failure of sigma to co-purify efficiently with core enzyme during phase partitioning.The loss of sigma activity and the weak binding of sigma to core enzyme occurs normally in a mutant blocked at an intermediate stage of sporulation (SpoII-4Z) and in wild-type bacteria sporulating in 121B medium, Difco sporulation medium, or Sterlini-Mandelstam resuspension medium. In contrast, sigma in two mutants (SpoOa-5NA and SpoOb-6Z) blocked at an early stage of spore formation remains active and tightly associated with RNA polymerase during stationary phase. 相似文献
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DNA sequence analysis suggests that expression of flagellar and chemotaxis genes in Escherichia coli and Salmonella typhimurium is controlled by an alternative sigma factor. 总被引:48,自引:6,他引:48
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J D Helmann M J Chamberlin 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(18):6422-6424
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Promoter architecture in the flagellar regulon of Bacillus subtilis: high-level expression of flagellin by the sigma D RNA polymerase requires an upstream promoter element. 总被引:5,自引:1,他引:5
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K Fredrick T Caramori Y F Chen A Galizzi J D Helmann 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(7):2582-2586
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Bacillus subtilis sigma factor sigma 29 is the product of the sporulation-essential gene spoIIG. 总被引:50,自引:7,他引:43
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J E Trempy C Bonamy J Szulmajster W G Haldenwang 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(12):4189-4192
Evidence is presented that the sporulation-essential locus spoIIG codes for both sigma 29 and a structurally related protein, P31. This demonstrates that at least one specific Bacillus subtilis RNA polymerase binding protein provides a critical function in endospore formation. spoIIG-specific RNA is present in B. subtilis cultures that are synthesizing P31 and sigma 29 and is absent in those that are not. A monoclonal antibody specific for an antigenic determinant on P31/sigma 29 detected crossreacting proteins (P25/P21) but not P31 or sigma 29 in a Spo- B. subtilis strain with a mutation at the spoIIG locus (spoIIG41). The appearance of P25 and P21 occurs in this mutant at a time when P31 and sigma 29 would normally appear and suggests that they are homologous proteins. Transformation of the spoIIG41 strain with plasmid DNA carrying the structural gene for spoIIG complements the Spo- phenotype and results in the synthesis of P31, sigma 29, P25, and P21 at the appropriate times during sporulation. In Escherichia coli, the cloned spoIIG sequence encoded a protein that reacted with the anti-P31/sigma 29 monoclonal antibody and had the electrophoretic mobility of authentic P31. 相似文献
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Products of nitrogen regulatory genes ntrA and ntrC of enteric bacteria activate glnA transcription in vitro: evidence that the ntrA product is a sigma factor. 总被引:110,自引:16,他引:94
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J Hirschman P K Wong K Sei J Keener S Kustu 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(22):7525-7529
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Two alkaline phosphatase genes positioned in tandem in Bacillus licheniformis MC14 require different RNA polymerase holoenzymes for transcription. 总被引:3,自引:0,他引:3
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F M Hulett P Z Wang M Sussman J W Lee 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(4):1035-1039
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Analysis of the Streptomyces coelicolor sigE gene reveals the existence of a subfamily of eubacterial RNA polymerase sigma factors involved in the regulation of extracytoplasmic functions. 总被引:18,自引:1,他引:17
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M A Lonetto K L Brown K E Rudd M J Buttner 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(16):7573-7577
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