Eukaryotic nirK genes encoding copper-containing nitrite reductase: originating from the protomitochondrion?

ABSTRACT: Although denitrification or nitrate respiration has been found among a few eukaryotes, its phylogenetic relationship with the bacterial system remains unclear because orthologous genes involved in the bacterial denitrification system were not identified in these eukaryotes. In this study, we isolated a gene from the denitrifying fungus Fusarium oxysporum that is homologous to the bacterial nirK gene responsible for encoding copper-containing nitrite reductase (NirK). Characterization of the gene and its recombinant protein showed that the fungal nirK gene is the first eukaryotic ortholog of the bacterial counterpart involved in denitrification. Additionally, recent genome analyses have revealed the occurrence of nirK homologs in many fungi and protozoa, although the denitrifying activity o

SUBMITTER: Kim SW 

PROVIDER: S-EPMC2681669 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature