Abstract
We have examined a variety of common mutagens in producing auxotrophic mutants in cowpea rhizobia strains JRC23 and IRC256. While NTG (N-methyl-N′-nitro-N-nitrosoguanidine), EMS (ethylmethane sulfonate), NA (nitrous acid), and UV (ultraviolet) irradiation were mutagenic with the strain JRC23, these mutagenic agents did not mutate strain IRC256. On the contrary, transposon mutagenesis with Tn5 yielded auxotrophs in strain IRC256 but not in strain JRC23, while only methionine (Met−) auxotrophs from strain JRC23, histidine (His−), and adenine plus thiamine (Ade−+Thi−) auxotrophs from strain IRC256 were isolated.
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McLaughlin, W., Ahmad, M.H. A note on auxotrophic mutants of cowpea rhizobia. Current Microbiology 15, 301–303 (1987). https://doi.org/10.1007/BF01577585
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DOI: https://doi.org/10.1007/BF01577585