Open AccessProperties of streptomycin dependent non‐nodulating mutants of cowpea rhizobia and Bradyrhizobium japonicum
Author(s) -
Ahmad M.H.,
Singh Inderpal
Publication year - 1987
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1987.tb02314.x
Subject(s) - rhizobia , streptomycin , mutant , biology , bradyrhizobium japonicum , microbiology and biotechnology , aminoglycoside , strain (injury) , bradyrhizobium , phenotype , rhizobiaceae , symbiosis , genetics , gene , rhizobium , antibiotics , bacteria , anatomy
We have isolated and characterized mutants from cowpea rhizobia strains JRW3 and IRC256 and Bradyrhizobium japonicum USDA110, which show dependence on streptomycin (Sm) for growth. In the presence of Sm, the majority of the Sm D (streptomycin dependent) mutants showed cross‐resistance to other aminoglycoside antibiotics and some showed no growth at 37°C and 40°C. When nodulation abilities of Sm D mutants (derived from all three strains) were examined, most of them (> 91%) showed non‐nodulating phenotypes to their respective hosts. Preliminary biochemical and genetic characterization indicated that drug‐uptake function was altered in Sm D mutant, and the wild type strain JRW3 could be transformed to streptomycin dependent by Sm D DNA.