Pichia pastoris 6-phosphofructokinase (PpPfk) is the most complex and probably largest (1 MDa) eukaryotic Pfk. It forms a dodecamer of four alpha-beta-gamma trimers. The gamma unit is unique, in contrast to other eukaryotic ATP-dependent 6-phosphofructokinases, and participates in oligomerization of the alpha and beta chains. It is not essential for enzymatic activity, but it modulates the allosteric behavior of the enzyme.