Identification of ATP-dependent phosphofructokinase as a regulatory step in the glycolytic pathway of the actinomycete Streptomyces coelicolor A 3(2)

The ATP-dependent phosphofructokinase (ATP-PFK) of Streptomyces coelicolor A3(2) was purified to homogeneity (1,600-fold) and characterized (110 kDa, with a single type of subunit of 40 kDa); it is allosterically inhibited by phosphoenolpyruvate. Cloning of the pfk gene of S. coelicolor A3(2) and analysis of the deduced amino acid sequence (343 amino acids; 36,667 Da) revealed high similarities to the PPi-PFK enzyme from Amycolatopsis methanolica (tetramer, nonallosteric; 70%) and to the allosteric ATP-PFK enzymes from other bacteria, e.g., Escherichia coli (tetramer; 37%) and Bacillus stearothermophilus (tetramer; 41%). Further structural and functional analysis of the two actinomycete PFK enzymes should elucidate the features of these proteins that determine substrate specificity (ATP versus PPi) and allosteric (in)sensitivity.