Abstract
The five glycolytic enzymes glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, phosphoglycerate mutase, enolase and pyruvate kinase were each purified from extracts of Zymomonas mobilis cells, by using dye-ligand chromatography as the principal step. Two procedures, producing three and two of the enzymes respectively, are described in detail. Z. mobilis glyceraldehyde-phosphate dehydrogenase was found to be similar in most respects to the enzyme from other sources, except for having a slightly larger subunit size. Phosphoglycerate kinase has properties typical for this enzyme; however, it did not show the sulphate activation effects characteristic of this enzyme from most other sources. Phosphoglycerate mutase is a dimer, partially independent of 2,3-bisphosphoglycerate, and has a high specific activity. Enolase was found to be octameric; otherwise its properties were very similar to those of the yeast enzyme. Pyruvate kinase is unusual in being dimeric, and not requiring K+ for activity. It is not allosterically activated by sugar phosphates, having a high activity in the absence of any effectors. Some quantitative differences in the relative amounts of these enzymes, compared with eukaryotic species, are ascribed to the fact that Z. mobilis utilizes the Entner-Doudoroff pathway rather than the more common Embden-Meyerhoff glycolytic route.