Abstract
Glucose-6-phosphate dehydrogenase was partially purified starting from the cell-free extract of Lactobacillus plantarum 11 and the properties of the dehydrogenase were investigated. The intracellular activity of the enzyme was calculated. Using kinetic data concerning the dehydrogenase activity in the presence of various concentrations of coenzyme, and inorganic ions, the activity of this enzyme under the conditions thought to be comparable with an intracytoplasmic environment was calculated to be 0.04μ moles per mg dry weight of cells per hr. This value was 1% of lactic acid forming activity of the intact cells. A similar quantitative relationship was also demonstrated between C14O2 and lactate which were produced from 1-C14-glucose by washed cells. The role of the dehydrogenase in the cells of this organism was discussed with respect to its relation to the homo-lactic acid fermentation.
