Genes encoding phosphofructokinases (PFK) from Escherichia coli and from the human muscle were expressed in PFK-deficient strains of Saccharomyces cerevisiae under the control of an inducible GAL1 promoter. They restored PFK activity under inducing conditions and complemented the galactose-negative growth phenotype of the recipient strains. The PFK enzymes expressed appear to be stable in yeast. The human muscle enzyme crossreacts with specific antibodies and shows the expected subunit size. As expected, its activity can be activated by fructose-2,6-bisphosphate, in contrast to the bacterial enzyme.
