Kakuo Kitahara

Quantitative Studies on Glycolytic Enzymes in Lactobacillus plantarum: Part IV. Intracellular Activity of Forward Reaction of Glyceraldehyde-3-phosphate Dehydrogenase during Glucose FermentationPart V Enzymatic Basis of Oxygen Independency on Lactic Acid Fermentation

The intracellular activity of glyceraldehyde-3-phosphate dehydrogenase was estimated. The dehydrogenase was purified about 70-fold by ammonium sulfate fractionation and DEAE cellulose chromatography. Basal properties of the purified enzyme were examined. From the activity of the enzyme in the sonicate, the intracellular activity was calculated by correcting the value for the intracellular conditions which were known previously. The intracellular activity of the dehydrogenase was found to be nearly equal to that of the lactate-forming activity from glucose in original washed cells, showing a significant participation of the dehydrogenase in the metabolic pathway of lactic acid fermentation in this organism.

Studies on Bacterial Cell Multiplication

Chemical composition of the filamentous cells of Lactobacillus delbrueckii produced by vitamin B12 deficient culture was studied. Protein and RNA contents per unit cell volume of the filamentous cells were nearly equal to those of normal cells, but the DNA content was much reduced. A cytoplast of the filamentous cell possessed about twice as large volume as that of the normal cell. A cytoplast of either filamentous or normal cell seems to contain the same amount of DNA. DNA level and membrane formation necessary for cell division remained as future problems.