Isolation and characterization of transposon-induced chlorate resistant mutants of the cyanobacterium Anabaena species PCC 7120

Abstract

Mutants of Anabaena sp. PCC 7120 resistant to chlorate were isolated using transposon mutagenesis. The Anabaena population of 5 x 107 cells ml-1 and log phase Escherichia coli cultures in undisturbed conditions produced maximum exconjugants. Nitrate-promoted growth and cellular constituents observed in the parent were absent in the mutants. Nitrate repressed heterocyst formation and N2-fixation in the parent, but had little or no effect on the mutants.