title: Expression of the N2 fixation gene operon of Paenibacillus sp. WLY78 under the control of the T7 promoter in Escherichia coli BL21.
abstract: OBJECTIVE
  To investigate the transcription and translation and nitrogenase activity of the nine N2-fixing-gene (nif) operon (nifBHDKENXhesAnifX) of Paenibacillus sp. WLY78 under the control of the T7 promoter in Escherichia coli BL21 under different conditions.
  
  
  RESULTS
  The Paenibacillus nif operon under the control of the T7 promoter is significantly transcribed and effectively translated in E. coli BL21 when grown in medium containing organic N compounds (yeast extract and Tryptone) or NH4+ by using RT-PCR and Western blot analysis. Transcription and translation of foreign nif genes in E. coli are not inhibited by environmental organic or inorganic N compounds or O2. However, contrary to transcription and translation, nitrogenase activity is 4% lower in the recombinant E. coli 78-32 compared to the native Paenibacillus sp. WLY78.
  
  
  CONCLUSIONS
  The Paenibacillus nif operon under the control of T7 promoter enables E. coli BL21 to synthesize active nitrogenase. This study shows how the nif gene operon can be transferred to non-N2-fixing bacteria or to eukaryotic organelles.
authors.affiliation: State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing, 100193, People's Republic of China. zhangyongyuan0@163.com.|College of Life Science, Shanxi Normal University, Linfen, 041000, Shanxi, China. zhangyongyuan0@163.com.
authors.forename: Lihong
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing, 100193, People's Republic of China. liuxiaomeng_1978@163.com.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing, 100193, People's Republic of China. lixinxin_1978@163.com.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing, 100193, People's Republic of China. sanfengchen0@163.com.
authors.forename: Sanfeng
authors.initials: S
authors.lastname: Chen
mesh_terms: D017123:Bacteriophage T7 / Q000235:genetics*; D015153:Blotting, Western; D003470:Culture Media / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D020869:Gene Expression Profiling; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D017672:Nitrogen Compounds / Q000378:metabolism; D009586:Nitrogen Fixation; D009876:Operon; D056507:Paenibacillus / Q000201:enzymology* / Q000235:genetics; D011401:Promoter Regions, Genetic; D060888:Real-Time Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D003470:Culture Media; D017672:Nitrogen Compounds; D011994:Recombinant Proteins
keywords: Escherichia coli; Nif gene operon; Nitrogenase activity; Paenibacillus; T7 promoter