Genetic diversity of nifH gene sequences in paenibacillus azotofixans strains and soil samples analyzed by denaturing gradient gel electrophoresis of PCR-amplified gene fragments.

ABSTRACT: The diversity of dinitrogenase reductase gene (nifH) fragments in Paenibacillus azotofixans strains was investigated by using molecular methods. The partial nifH gene sequences of eight P. azotofixans strains, as well as one strain each of the close relatives Paenibacillus durum, Paenibacillus polymyxa, and Paenibacillus macerans, were amplified by PCR by using degenerate primers and were characterized by DNA sequencing. We found that there are two nifH sequence clusters, designated clusters I and II, in P. azotofixans. The data further indicated that there was sequence divergence among the nifH genes of P. azotofixans strains at the DNA level. However, the gene products were more conserved at the protein level. Phylogenetic analysis showed that all nifH cluster II sequences were similar t

SUBMITTER: Rosado AS 

PROVIDER: S-EPMC106771 | biostudies-literature | 1998 Aug

REPOSITORIES: biostudies-literature