title: Genetic analysis of Azotobacter vinelandii mutant strains unable to fix nitrogen.
abstract: Transformation was used to perform ratio test crosses with mutant strains of Azotobacter vinelandii unable to fix N2. Mutations that simultaneously eliminated both components of nitrogenase (nif-1 and nif-2) were tightly linked. The nif-45 mutation that resulted in the absence of an active molybdenum cofactor was closer to nif-1 and nif-2 than to any of the other nif mutations. Strains that lacked component I carried mutations that were closely linked to each other. Mutations that probably were located in the structural genes for components I and II appeared to be relatively close to each other on the A. vinelandii genome.
mesh_terms: D001395:Azotobacter / Q000235:genetics* / Q000378:metabolism; D003433:Crosses, Genetic; D005798:Genes, Bacterial; D009154:Mutation; D009586:Nitrogen Fixation; D009591:Nitrogenase / Q000235:genetics
chemical_list: D009591:Nitrogenase