Localization of denitrification genes on the chromosomal map of Pseudomonas aeruginosa

Microbiology. 1998 Feb;144 ( Pt 2):441-8. doi: 10.1099/00221287-144-2-441.


Cleavage of chromosomal DNA from Pseudomonas aeruginosa PAO by Spel and Dpnl has been used together with PFGE and Southern hybridization to establish the map location of the following principal denitrification genes: narGH (encoding the large and small subunits of respiratory nitrate reductase), nirS (cytochrome-cd1 nitrite reductase), nirE (uroporphyrinogen-III methyltransferase for haem d1 biosynthesis), norCB (nitric-oxide reductase complex), nosZ (nitrous-oxide reductase) and nosA (an outer-membrane protein and OprC homologue). The study also included several genes related to anaerobic or microaerophilic metabolism: napA (encoding the catalytic subunit of the periplasmic nitrate reductase), ccoN (catalytic subunit of the cytochrome-cbb3 oxidase), hemN (oxygen-independent coproporphyrinogen-III oxidase), an fnr-like regulatory gene, and azu and fdxA (electron carriers azurin and ferredoxin, respectively). Genes necessary for denitrification are concentrated at 20 to 36 min on the P. aeruginosa chromosome, where they form three separate loci, the nir-nor, nar and nos gene clusters. Genomic DNA of Pseudomonas stutzeri ZoBell was also subjected to Spel restriction and Southern analysis to assign denitrification genes to individual fragments. A homologue of nosA encoding a putative component of the Cu-processing apparatus for nitrous-oxide reductase was identified. In both P. aeruginosa and P. stutzeri there is evidence for the linkage of anr (fnrA) with hemN and ccoN; and for the presence of a napA gene.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Azurin / genetics
  • Bacterial Proteins / genetics
  • Chromosome Mapping*
  • Coproporphyrinogen Oxidase*
  • DNA Probes
  • Deoxyribonucleases, Type II Site-Specific / metabolism
  • Electron Transport Complex IV / genetics
  • Escherichia coli Proteins*
  • Ferredoxins / genetics
  • Genes, Bacterial*
  • Genome, Bacterial
  • Iron-Sulfur Proteins / genetics
  • Methyltransferases / genetics
  • Multigene Family
  • Nitrate Reductase
  • Nitrate Reductases / genetics
  • Nitrogen / metabolism*
  • Oxidoreductases / genetics
  • Periplasm / enzymology
  • Periplasm / genetics
  • Plasmids
  • Porins / genetics
  • Pseudomonas aeruginosa / genetics*
  • Pseudomonas aeruginosa / metabolism*


  • Bacterial Proteins
  • DNA Probes
  • Escherichia coli Proteins
  • FNR protein, E coli
  • Ferredoxins
  • Iron-Sulfur Proteins
  • OprC protein, Pseudomonas aeruginosa
  • Porins
  • Azurin
  • Oxidoreductases
  • duroquinol oxidase
  • HemN protein, Bacteria
  • Coproporphyrinogen Oxidase
  • Nitrate Reductases
  • nitrous oxide reductase
  • nitric-oxide reductase
  • Nitrate Reductase
  • Electron Transport Complex IV
  • Methyltransferases
  • uroporphyrin-III C-methyltransferase
  • endodeoxyribonuclease SpeI
  • Deoxyribonucleases, Type II Site-Specific
  • Nitrogen