1-phosphofructokinase (FruK), minor 6-phosphofructokinase (pfkB) and related sugar kinases. FruK plays an important role in the predominant pathway for fructose utilisation.This group also contains tagatose-6-phophate kinase, an enzyme of the tagatose 6-phosphate pathway, which responsible for breakdown of the galactose moiety during lactose metabolism by bacteria such as L. lactis.