title: A DNA fragment hybridizing to a nif probe in Rhodobacter capsulatus is homologous to a 16S rRNA gene.
abstract: We have sequenced the Rhodobacter capsulatus nifH and nifD genes. The nifH gene, which codes for the dinitrogenase reductase protein, is 894 bp long and codes for a polypeptide of predicted Mr 32,412. The nifD gene, which codes for the alpha subunit of dinitrogenase, is 1,500 bp long and codes for a protein of predicted Mr 56,113. A 776-bp BglII-XhoI fragment containing only nif sequences was used as a hybridization probe against R. capsulatus genomic DNA. Two HindIII fragments, 11.8 kb and 4.7 kb in length, hybridize to this probe. Both fragments have been cloned from a cosmid library. The 11.8-kb fragment contains the nifH, D and K genes, as previously demonstrated (Scolnik and Haselkorn, 1984). In this paper we present evidence that suggests that the 4.7-kb HindIII fragment contains a gene coding for 16S rRNA, and that although homology between nif and this fragment can be observed in filter hybridization experiments, a second copy of the nif structural genes seems not to be present in this region.
mesh_terms: D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial; D009154:Mutation; D012335:RNA, Ribosomal / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D012241:Rhodopseudomonas / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; D012335:RNA, Ribosomal