title: Isolation of pigmentation mutants of the green filamentous photosynthetic bacterium Chloroflexus aurantiacus.
abstract: Mutants deficient in the production of bacteriochlorophyll c (Bchl c) and one mutant lacking colored carotenoids were isolated from the filamentous gliding bacterium Chloroflexus aurantiacus. Mutagenesis was achieved by using UV radiation or N-methyl-N'-nitro-N-nitrosoguanidine. Several clones were isolated that were deficient in Bchl c synthesis. All reverted. One double mutant deficient both in Bchl c synthesis and in the synthesis of colored carotenoids under anaerobic conditions was isolated. Isolation of a revertant in Bchl c synthesis from this double mutant produced a mutant strain of Chloroflexus that grew photosynthetically under anaerobic conditions and lacked colored carotenoids. Analysis of pigment contents and growth rates of the mutants revealed a positive association between growth rate and content of Bchl c under light-limiting conditions.
mesh_terms: D000900:Anti-Bacterial Agents / Q000633:toxicity; D001419:Bacteria / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D008769:Methylnitronitrosoguanidine / Q000633:toxicity; D009154:Mutation; D010788:Photosynthesis; D010860:Pigments, Biological / Q000302:isolation & purification*; D014466:Ultraviolet Rays
chemical_list: D000900:Anti-Bacterial Agents; D010860:Pigments, Biological; D008769:Methylnitronitrosoguanidine