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Phylogeny of nitrogenase sequences in Frankia and other nitrogen-fixing microorganisms.

Authors :
Normand, Philippe
Bouquet, Jean
Source :
Journal of Molecular Evolution; 1989, Vol. 29 Issue 5, p436-447, 12p
Publication Year :
1989

Abstract

The complete nucleotide sequence of a nitrogenase ( nifH) gene was determined from a second strain (HRN18a) of Frankia, an aerobic soil bacterium. The open reading frame is 870 bp long and encodes a polypeptide of 290 amino acids. The amino acid and nucleotide sequences were compared with 21 other published sequences. The two Frankia strains were 96% similar at the amino acid level and 93% similar at the nucleotide level. A number of methods were used to infer phylogenies of these nitrogen fixers, based on nifH amino acid and nucleotide sequences. The results obtained do not agree completely with other phylogenies for these bacteria and thus make probable occurrences of lateral transfer of the nif genes. The time of divergence of the two Frankia strains could be estimated at about 100 million years. The vanadium-dependent (Type 2) nitrogenase present in Azotobacter spp. appears to be a recent derivation from the conventional molybdenum-dependent (Type 1) enzyme, whereas the iron-dependent (Type 3) alternative nitrogenase would have a much older origin. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
00222844
Volume :
29
Issue :
5
Database :
Complementary Index
Journal :
Journal of Molecular Evolution
Publication Type :
Academic Journal
Accession number :
70630610
Full Text :
https://doi.org/10.1007/BF02602914