Mutations affecting gluconate catabolism in Escherichia coli. Genetic mapping of loci for the low affinity transport and the thermoresistant gluconokinase

The isolation and properties of strains of Escherichia coli carrying mutations affecting either the low affinity transport for gluconate (gene gntU) or the thermoresistant gluconokinase (gene gntK) are described. A lesion of each type was genetically characterized by transduction experiments. Both mutations mapped in the asd region, and the order was malA-glpD-asd-gntU-gntK, with the last two markers at about min 75.78 and 75.86 on the map, respectively. Mutations altering specifically gntU have not been previously reported.