Immunocytochemical localization of glycolytic and fermentative enzymes in Zymomonas mobilis

Abstract

Gold-labeled antibodies were used to examine the subcellular locations of 11 glycolytic and fermentative enzymes in Zymomonas mobilis. Glucose-fructose oxidoreductase was clearly localized in the periplasmic region. Phosphogluconate lactonase and alcohol dehydrogenase I were concentrated in the cytoplasm near the plasma membrane. The eight remaining enzymes were more evenly distributed within the cytoplasmic matrix. Selected enzyme pairs were labeled on opposite sides of the same thin section to examine the frequency of colocalization. Results from these experiments provide evidence that glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, and alcohol dehydrogenase I form an enzyme complex.