Genetic Map Position of the Gluconate-6-Phosphate Dehydrogenase Gene in<i>Salmonella typhimurium</i>

Abstract

Gluconate-6-phosphate dehydrogenase (GND) is genetically determined in Salmonella typhimurium by a locus (gnd) mapping between the somatic antigen (rfb) and histidine (his) operons. The enzyme is constitutive. Strains of Salmonella carrying an F' genetic element which contains the gnd(+) gene have GND activity two to three times that of the wild type. This gene dosage effect was used to determine that the GND reaction is not rate-limiting for the metabolism of glucose by the pentose shunt in S. typhimurium.