Abstract
The Bacillus subtilis L-42 mutant strain, which displays limited growth and inability to cope with hyper-osmotic shock in a defined media with a potassium concentration below 1mM, was isolated by non-specific transposon insertional mutagenesis. Localization of the mutation was provided, only one insertion of recombinant transposon was found in the mutant chromosome, localized into the yxkO gene, a putative ribokinase with unknown function.
The mutant reveals considering pleiotropic effect, is involved in adaptation to osmotic, K+ ions limitation stress, differ in morphology of colony growth. Further genetic and physiological characterizations of the mutant were done and it can be assumed that the product of the yxkO gene is involved in regulatory pathway of the general stress response to cope with heat, ethanol stresses and limiting concentration of potassium and osmotic up shift when no other compatible solute are available.