The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
Gene Review

nifH  -  nitrogenase reductase

Nostoc sp. PCC 7120

Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of nifH

  • The nifU-nifH intergenic region of Nostoc sp. strain MUN 8820 was sequenced (1,229 bp) and was approximately 95% identical to the equivalent region in N. commune UTEX 584 [1].
  • Comparison of the nifB 5'-flanking sequence with the nifH 5'-flanking sequence did not reveal any consensus base pairs that would define a nif promoter for Anabaena [2].
  • Phylogenetic analysis of nifH sequences tends to suggest that molybdenum nitrogenase 2 is characteristic of those unicellular or filamentous, nonheterocystous cyanobacteria fixing N2 under microaerobic conditions only [3].
  • The DNA sequence of a 359-bp fragment of nifH was determined for the heterocystous strains Anabaena sp. strain CA (ATCC 33047), Nostoc muscorum UTEX 1933, a Nostoc sp., Gloeothece sp. strain ATCC 27152, Lyngbya lagerheimii UTEX 1930, and Plectonema boryanum IU 594 [4].
  • A region of DNA 1 kilobase upstream from the 5' end of nifH showed considerable sequence similarity to part of the published nifU sequences of Azotobacter vinelandii and Klebsiella pneumoniae [5].

High impact information on nifH

  • Under iron stress but in the presence of combined nitrogen, fdxH and nifH genes were transcriptionally active; although excision of the 11-kb element seemed to be completed, nitrogenase activity and the fdxH gene product were not detectable [6].
  • The nifK gene was not transcribed in DW12-2.2, indicating that its expression is dependent on the nifH promoter and excision of the 11-kb element from the operon [7].
  • Southern analysis of LW1 showed normal excision of the 11-kb element from the nifHDK operon, indicating that transcription from the nifH promoter is not required for the developmentally regulated DNA rearrangement [7].
  • A 1.68-kb DNA fragment containing the nifH promoter was deleted from the chromosome to produce the mutant strain LW1 [7].
  • The heterocystous cyanobacterium Nostoc commune UTEX 584 contains two nifH-like sequences (nifH1 and nifH2) in addition to nifHD [5].

Biological context of nifH


Other interactions of nifH


Analytical, diagnostic and therapeutic context of nifH

  • In contrast, the abundance of nifH sequences was approximately 7.5 times greater (per microgram of total DNA) in mature crusts than in poorly developed crusts at a given site as measured by quantitative PCR [12].


  1. GlbN (cyanoglobin) is a peripheral membrane protein that is restricted to certain Nostoc spp. Hill, D.R., Belbin, T.J., Thorsteinsson, M.V., Bassam, D., Brass, S., Ernst, A., Böger, P., Paerl, H., Mulligan, M.E., Potts, M. J. Bacteriol. (1996) [Pubmed]
  2. Nitrogen fixation (nif) genes of the cyanobacterium Anabaena species strain PCC 7120. The nifB-fdxN-nifS-nifU operon. Mulligan, M.E., Haselkorn, R. J. Biol. Chem. (1989) [Pubmed]
  3. Bacterial life and dinitrogen fixation at a gypsum rock. Boison, G., Mergel, A., Jolkver, H., Bothe, H. Appl. Environ. Microbiol. (2004) [Pubmed]
  4. Detection and characterization of cyanobacterial nifH genes. Ben-Porath, J., Zehr, J.P. Appl. Environ. Microbiol. (1994) [Pubmed]
  5. Cloning of nifHD from Nostoc commune UTEX 584 and of a flanking region homologous to part of the Azotobacter vinelandii nifU gene. Defrancesco, N., Potts, M. J. Bacteriol. (1988) [Pubmed]
  6. Transcriptional and translational analysis of ferredoxin and flavodoxin under iron and nitrogen stress in Anabaena sp. strain PCC 7120. Razquin, P., Schmitz, S., Fillat, M.F., Peleato, M.L., Böhme, H. J. Bacteriol. (1994) [Pubmed]
  7. Independent regulation of nifHDK operon transcription and DNA rearrangement during heterocyst differentiation in the cyanobacterium Anabaena sp. strain PCC 7120. Golden, J.W., Whorff, L.L., Wiest, D.R. J. Bacteriol. (1991) [Pubmed]
  8. Developmental rearrangement of cyanobacterial nif genes: nucleotide sequence, open reading frames, and cytochrome P-450 homology of the Anabaena sp. strain PCC 7120 nifD element. Lammers, P.J., McLaughlin, S., Papin, S., Trujillo-Provencio, C., Ryncarz, A.J. J. Bacteriol. (1990) [Pubmed]
  9. Analysis of the sequences within and flanking the cyanoglobin-encoding gene, glbN, of the cyanobacterium Nostoc commune UTEX 584. Angeloni, S.V., Potts, M. Gene (1994) [Pubmed]
  10. Three distinct clades of cultured heterocystous cyanobacteria constitute the dominant N-fixing members of biological soil crusts of the Colorado Plateau, USA. Yeager, C.M., Kornosky, J.L., Morgan, R.E., Cain, E.C., Garcia-Pichel, F., Housman, D.C., Belnap, J., Kuske, C.R. FEMS Microbiol. Ecol. (2007) [Pubmed]
  11. Cloning and transcriptional analysis of the nifUHDK genes of Trichodesmium sp. IMS101 reveals stable nifD, nifDK and nifK transcripts. Dominic, B., Chen, Y.B., Zehr, J.P. Microbiology (Reading, Engl.) (1998) [Pubmed]
  12. Diazotrophic community structure and function in two successional stages of biological soil crusts from the Colorado Plateau and Chihuahuan Desert. Yeager, C.M., Kornosky, J.L., Housman, D.C., Grote, E.E., Belnap, J., Kuske, C.R. Appl. Environ. Microbiol. (2004) [Pubmed]
WikiGenes - Universities