title: Genome rearrangement and nitrogen fixation in Anabaena blocked by inactivation of xisA gene.
abstract: Two genome rearrangements involving 11- and 55-kilobase DNA elements occur during the terminal differentiation of an Anabaena photosynthetic vegetative cell into a nitrogen-fixing heterocyst. The xisA gene, located on the nifD 11-kilobase DNA element, was inactivated by recombination between the chromosome and a copy of the xisA gene that was mutated by inserting an antibiotic gene cassette. Site-directed inactivation of the Anabaena xisA gene blocked rearrangement of the 11-kilobase element and nitrogen fixation, but did not affect rearrangement of the 55-kilobase element, heterocyst differentiation, or heterocyst pattern formation.
mesh_terms: D000458:Cyanobacteria / Q000235:genetics* / Q000254:growth & development; D004247:DNA / Q000235:genetics; D015321:Gene Rearrangement; D005796:Genes; D005798:Genes, Bacterial; D015151:Immunoblotting; D009586:Nitrogen Fixation / Q000235:genetics*; D010641:Phenotype; D015183:Restriction Mapping
chemical_list: D004247:DNA