title: Phylogeny and characterization of three nifH-homologous genes from Paenibacillus azotofixans.
abstract: In this paper, we report the cloning and characterization of three Paenibacillus azotofixans DNA regions containing genes involved in nitrogen fixation. Sequencing analysis revealed the presence of nifB1H1D1K1 gene organization in the 4,607-bp SacI DNA fragment. This is the first report of linkage of a nifB open reading frame upstream of the structural nif genes. The second (nifB2H2) and third (nifH3) nif homologues are confined within the 6,350-bp HindIII and 2,840-bp EcoRI DNA fragments, respectively. Phylogenetic analysis demonstrated that NifH1 and NifH2 form a monophyletic group among cyanobacterial NifH proteins. NifH3, on the other hand, clusters among NifH proteins of the highly divergent methanogenic archaea.
authors.affiliation: School of Biological Sciences, Universiti Sains Malaysia, 11800 Pulau Pinang, Malaysia.
authors.forename: Quok-Cheong
authors.initials: QC
authors.lastname: Choo
authors.forename: Mohd-Razip
authors.initials: MR
authors.lastname: Samian
authors.forename: Nazalan
authors.initials: N
authors.lastname: Najimudin
mesh_terms: D000595:Amino Acid Sequence; D001406:Bacillaceae / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D010088:Oxidoreductases; C029130:nitrogenase reductase