Studies of protein-protein interaction using countercurrent distribution in aqueous two-phase systems: partition behavior of five glycolytic enzymes from crude baker's yeast extract

The partition behavior of five glycolytic enzymes, in extracts from baker's yeast (Saccharomyces cerevisiae), between two aqueous phases has been studied by countercurrent distribution. All enzymes showed distribution patterns which indicated homogeneity and a similar partition behavior. In purified form, three of the enzymes (glyceraldehyde-phosphate dehydrogenase, 3-phosphoglycerate kinase, and enolase) showed the same partition behavior as in the extracts. Pure 6-phosphofructokinase, on the other hand, changed its partition distinctively relative to what was found in the extracts. These results indicate interactions between this enzyme and macromolecular compounds in the extracts and support a model suggested by Kurganov et al. (1985, J. Theor. Biol. 116, 509-526) describing a "glycolytic particle."